First-Time DM Mistakes (And Exactly How to Fix Them)
Every experienced Dungeon Master has a mental collection of cringe-worthy moments from their early sessions. Learning about new DM mistakes to avoid before you make them gives you an enormous advantage over the trial-and-error approach that frustrated previous generations of game masters.
The good news is that beginner DM mistakes follow predictable patterns. The same errors show up regardless of whether you’re running for friends, family, or strangers—and every single one has concrete solutions that experienced DMs have refined over decades of collective gameplay.
This guide identifies the most common and damaging first time DM tips violations, explains why each mistake happens, and provides specific actionable fixes you can implement immediately. You’ll still make some mistakes because that’s how learning works, but you’ll avoid the ones that kill campaigns and frustrate players.
Mistake #1: Over-Preparing Everything
New DMs often spend 10-20 hours preparing for a 3-hour session, creating detailed histories for every NPC, mapping every building in town, and planning for contingencies that will never occur.
Why This Happens
Fear of being caught unprepared drives excessive preparation. You imagine players asking about the blacksmith’s childhood, the innkeeper’s political views, or the specific trade goods in that merchant cart. You want answers ready for everything.
Additionally, preparation feels productive and safe. You control what you create beforehand. The unpredictable chaos of actual play feels threatening by comparison.
Why It’s a Problem
Players will ignore 70-80% of your prepared content. That elaborate backstory for the shopkeeper? Players buy their gear and leave without asking a single question. Those three alternative dungeon paths? They take the first one and never see the others.
Meanwhile, you’ve exhausted yourself preparing content nobody experiences while leaving yourself depleted for the actual session. Burnout from over-preparation kills more campaigns than bad DMing does.
Exactly How to Fix It
Adopt the “Three Things” preparation method: prepare three interesting NPCs, three potential encounters, and three locations or set pieces. That’s it. Everything else you improvise.
For each session, know: the opening hook (how does the session start?), the potential climax (what’s the main encounter or challenge?), and the session-ending hook (what pulls players toward next session?).
Time-box your preparation. Set a timer for 60 minutes. When it rings, stop preparing regardless of how “complete” things feel. You have enough. Trust yourself to improvise the rest.
Keep a “random tables” document with NPC names, shop inventories, and encounter ideas. When players ask unexpected questions, roll or pick from your tables instead of making things up cold.
Mistake #2: Railroading Players Into Your Story
You’ve prepared an exciting adventure where players investigate the merchant, discover his criminal connections, and confront him at the warehouse. But players decide to report the merchant to the city guard and let authorities handle it. You panic and force them back onto your planned path.
Why This Happens
You invested significant effort into your prepared story. Watching players ignore it feels like wasted work. Additionally, improvising alternative paths feels scary when you don’t know what happens next.
New DMs often think of themselves as authors writing stories that players experience. This mental model leads to frustration when players don’t follow the script.
Why It’s a Problem
Player agency—the ability to make meaningful choices that affect outcomes—is the core appeal of tabletop RPGs. When choices don’t matter because the DM forces predetermined outcomes, players lose investment. Why bother strategizing if the DM will just make whatever they want happen anyway?
Players notice railroading even when you think you’re being subtle. “The city guard refuses to help” or “The merchant has already fled before you can report him” transparently serve to force your preferred path.
Exactly How to Fix It
Shift your mental model from “author” to “world simulator.” You’re not writing a story—you’re establishing situations and letting players determine outcomes through their choices.
Prepare situations, not plots. Instead of “players will investigate the merchant and confront him at the warehouse,” prepare “the merchant is running a criminal operation from his warehouse. He has X guards, Y security measures, and Z goals. What happens depends on what players do.”
When players choose unexpected approaches, ask yourself: “What would realistically happen if they did this?” If they report to the city guard, maybe the guard investigates (slowly, giving the merchant time to destroy evidence), or maybe the guard is corrupt and tips off the merchant, or maybe the guard handles it and players miss out on rewards but the problem gets solved.
Let player choices have real consequences, even when those consequences mean your prepared content doesn’t get used. That unused warehouse encounter can be repurposed for a different location later.
Mistake #3: Saying “No” Instead of “Yes, But”
Player: “I want to swing from the chandelier and kick the guard in the face.”
New DM: “There’s no chandelier in this room.”
Player: “Can I try to convince the dragon to let us pass?”
New DM: “Dragons can’t be reasoned with.”
Why This Happens
New DMs feel responsible for maintaining “realistic” worlds and “balanced” encounters. When players propose creative solutions, the instinct is to shut them down to preserve whatever you’d prepared.
There’s also fear that saying yes to creative ideas will break the game or make things too easy.
Why It’s a Problem
D&D thrives on creative problem-solving. When players learn their creative ideas get rejected, they stop proposing them. Sessions become mechanical—players only attempt “standard” actions because those are the only ones that work.
Worse, constant rejection makes players feel adversarial toward you. They’re trying to have fun and you keep blocking them.
Exactly How to Fix It
Default to “Yes, and…” or “Yes, but…” instead of “No.”
“I want to swing from the chandelier” becomes “Yes, there’s a chandelier—make an Athletics check to swing across. DC 12, but if you fail you’ll fall prone at the guard’s feet.”
“Can I convince the dragon?” becomes “You can certainly try. This dragon is proud and greedy—what approach are you taking? Roll Persuasion, but know that failure might anger it.”
The “but” introduces risk or complication that maintains challenge without blocking creativity. Players feel rewarded for creative thinking while still facing meaningful obstacles.
Reserve “No” for genuinely impossible or world-breaking requests. “Can I teleport to the moon?” deserves a no. “Can I try talking to the hostile orc before combat starts?” deserves a yes.
Mistake #4: Making Combat Too Easy or Too Hard
Your carefully designed boss fight ends in two rounds when players nova their best abilities. Or your “easy” encounter nearly kills the entire party when dice go badly and you underestimated enemy damage.
Why This Happens
D&D’s encounter balancing guidelines are notoriously unreliable. “Deadly” encounters sometimes feel easy. “Medium” encounters sometimes kill characters. The math depends heavily on party composition, player skill, dice luck, and factors the rules can’t account for.
New DMs also struggle to predict how player abilities combine or how action economy affects outcomes.
Why It’s a Problem
Trivially easy combats bore players and remove tension. Why fear anything if every fight ends quickly without real danger? Conversely, unexpectedly deadly combats feel unfair, especially early in campaigns before players have invested heavily in characters.
Both extremes undermine the feeling that player choices and tactics matter.
Exactly How to Fix It
Use encounter calculators (Kobold Fight Club, D&D Beyond encounter builder) as starting points, not gospel. They help you avoid massive miscalculations but can’t guarantee perfect balance.
Start encounters slightly easier than you think appropriate for your first few sessions. You can always add reinforcements or have enemies use smarter tactics mid-combat. Reducing difficulty mid-fight is much harder to do subtly.
Learn to adjust on the fly. If combat is too easy, enemies call for reinforcements, reveal hidden abilities, or fight more intelligently. If combat is too deadly, enemies flee when bloodied, make tactical mistakes, or focus on objectives other than killing players.
Track your party’s capabilities: what’s their average damage per round? What’s their AC range? How many hit points do they have? Knowing these numbers helps you predict outcomes.
After sessions, note which encounters worked and which didn’t. Your specific group’s capabilities may differ significantly from theoretical averages.
Mistake #5: Not Giving Players Enough Information
You describe the room: “You enter a chamber with stone walls.” Players wander around aimlessly, missing the hidden door, the important inscription, and the trap trigger because you didn’t mention them and they didn’t ask the right questions.
Why This Happens
New DMs worry about “giving away” too much information, ruining puzzles, or making things too easy. They treat knowledge as a reward players must earn through correct questions.
There’s also the “curse of knowledge” problem—you know the hidden door exists, so you assume it’s obvious. But players only know what you tell them.
Why It’s a Problem
Players can’t make meaningful decisions without information. If they don’t know options exist, they can’t choose them. “Investigate the mysterious inscription” requires knowing the inscription exists.
Withholding basic information creates frustrating guessing games where players try to ask the “right” question to unlock the content you’re hiding.
Exactly How to Fix It
Describe everything player characters would reasonably notice upon entering a space. If there’s a door, mention the door. If there’s an inscription, mention strange markings on the wall. If the air smells wrong, say so.
Use the “three clue rule” for important information: any crucial fact should be discoverable through at least three different approaches. The hidden door might be found by searching walls (Investigation), noticing draft (Perception), or asking local NPCs about the room’s history.
Volunteer information when players investigate generally. “I search the room” should reveal notable features, not require separate checks for every object. Save detailed investigation for specific items or hidden secrets.
When in doubt, give more information rather than less. Players having too much information rarely breaks games. Players having too little information creates frustrating dead ends.
Mistake #6: Letting One Player Dominate
Your most confident player speaks first, speaks loudest, and makes decisions for the group. Quieter players sit back and let them handle everything. An hour passes and two players haven’t spoken at all.
Why This Happens
Confident players naturally fill silence. They’re not trying to dominate—they’re just comfortable taking initiative. Meanwhile, quieter players may be unsure whether speaking up is appropriate, waiting for invitation, or simply processing more slowly.
New DMs often appreciate the confident player because they drive action forward and reduce awkward silences.
Why It’s a Problem
Quiet players came to play D&D too. If one player handles everything, others become spectators rather than participants. They lose investment and eventually stop showing up.
The dominating player also misses chances to see what other players bring to the table. Party dynamics become one-dimensional.
Exactly How to Fix It
Directly invite quiet players to contribute. “Thorin, what does your character think about this plan?” or “Elara, you’ve been watching this conversation—does your character have any concerns?”
Create situations that require different characters’ skills. The confident fighter can’t pick locks, so the quiet rogue must step forward. The loud bard can’t read arcane inscriptions, so the shy wizard must contribute.
Establish table norms: “Let’s hear from everyone before we finalize the plan” or “Go around the table—what’s each character doing during this investigation?”
Talk to the dominating player privately if the problem persists. They’re usually unaware and happy to step back once you explain. “Hey, you’re doing great, but I want to make sure everyone gets spotlight time. Can you help me draw out the quieter players?”
Mistake #7: Inconsistent Rulings
Last session, you allowed the rogue to hide in plain sight with a good Stealth roll. This session, you require cover for hiding. Players get confused and frustrated because the rules seem to change arbitrarily.
Why This Happens
New DMs make rulings on the fly without tracking them. Each situation feels unique in the moment. You don’t remember how you ruled previously, or you’ve since learned the “correct” rule and want to apply it.
Why It’s a Problem
Inconsistency feels unfair. Players can’t strategize when they don’t know what rules apply. “That worked last time!” arguments derail sessions and create resentment.
Inconsistency also signals that DM whim trumps established expectations, making players feel their characters’ abilities are unreliable.
Exactly How to Fix It
Keep a “house rules” document that records rulings as you make them. “Hiding requires at least partial cover. Ruled this in Session 3.” When similar situations arise, check your document.
If you want to change a previous ruling, announce it between sessions: “I’ve been thinking about hiding rules, and I want to handle it differently going forward. Starting next session, you’ll need cover to attempt Stealth in combat.”
When making rulings, briefly explain your reasoning: “I’m requiring cover because otherwise hiding becomes too easy. Does that seem fair?” This transparency helps players understand and accept decisions.
Accept that some inconsistency is inevitable. When players catch you, acknowledge it gracefully: “You’re right, I ruled that differently before. Let’s use [your preferred ruling] consistently going forward, starting now.”
Mistake #8: Running Monsters Suboptimally
Every enemy fights to the death, standing in place and trading blows with whoever engaged them first. Goblins use the same tactics as dragons. Intelligent enemies make obviously stupid decisions.
Why This Happens
Running monsters tactically while simultaneously managing everything else overwhelms new DMs. It’s easier to have enemies attack whoever’s closest and fight until dead.
There’s also reluctance to “pick on” players by having enemies make smart targeting decisions.
Why It’s a Problem
Stupid enemies make combat boring and predictable. Players don’t need tactics when enemies obligingly line up for area spells and ignore obvious threats like the wizard concentrating on Hypnotic Pattern.
Combat stops feeling dangerous when enemies never exploit weaknesses or create tactical problems.
Exactly How to Fix It
Give each enemy type a simple tactical identity: goblins try to gang up on isolated targets, wolves circle and flank, cultists protect their leader, bandits flee when losing. Write these down for reference.
Have enemies respond logically to threats. The goblin who just watched the wizard kill three friends with Burning Hands will target that wizard next. The bandit captain will call retreat when clearly losing.
Use enemy intelligence scores as guidance. INT 7 goblins use pack tactics but fall for simple tricks. INT 16 wizards anticipate player strategies and counter them.
Not every enemy fights to the death. Morale breaks. Enemies flee, surrender, or negotiate. This creates variety and makes the enemies who DO fight to the death feel more threatening.
Mistake #9: Forgetting to Make NPCs Memorable
Players meet the blacksmith, the innkeeper, and the merchant. All three speak in your normal voice, give information when asked, and fade from memory immediately. When you reference them later, players ask “Who?”
Why This Happens
New DMs focus on NPC function (gives quest, sells items, provides information) rather than personality. You’re tracking so many things that distinctive characterization falls to the bottom of priorities.
There’s also reluctance to do “silly voices” or worried that attempts at characterization will seem amateur.
Why It’s a Problem
Forgettable NPCs make the world feel hollow. Players don’t care about people they can’t distinguish. When villains threaten unnamed shopkeeper #7, there’s no emotional stakes.
Conversely, memorable NPCs create investment. Players remember the grumpy dwarf blacksmith who complained about adventurers and root for (or against) him.
Exactly How to Fix It
Give every recurring NPC exactly one distinctive trait: a speech pattern, physical quirk, strong opinion, or memorable goal. The innkeeper who ends every sentence with “you understand?” The merchant who haggles over every copper. The guard who desperately wants to be an adventurer.
You don’t need voice acting. Simple adjustments work: speak faster or slower, louder or softer, more formally or casually. “The blacksmith speaks in short, clipped sentences and never smiles” creates distinction without accents.
Write down NPC traits as you create them. When you need to roleplay them again, check your notes. Consistency builds memorability.
Reference NPCs by name and trait when they reappear: “You see Grimjaw the blacksmith, still scowling at customers.” This reminds players who they’re dealing with.
Mistake #10: Not Ending Sessions Properly
You glance at the clock, realize you’re out of time, and abruptly announce “Okay, we’ll stop here.” Players feel interrupted mid-scene without resolution or anticipation.
Why This Happens
Time management is genuinely difficult, especially when improvising. You lose track of time or underestimate how long remaining content will take.
There’s also uncertainty about what makes a “good” stopping point versus an arbitrary interruption.
Why It’s a Problem
Abrupt endings leave players unsatisfied. They wanted closure on the current scene, not interruption. Worse, they have nothing specific to anticipate before next session.
Poor session endings reduce excitement about returning. The campaign loses momentum.
Exactly How to Fix It
Set a “warning track” 30 minutes before your hard end time. When you hit that mark, start steering toward a stopping point rather than starting new content.
Identify good stopping points in advance: after major encounters resolve, when players reach new locations, upon significant discoveries, or at cliffhanger moments.
End sessions with a hook for next time: “As you catch your breath, you hear footsteps approaching from deeper in the dungeon” or “The merchant’s dying words reveal the name of his contact in the capital.” Give players something to anticipate.
Take 5 minutes after stopping point to wrap up: “Great session! Next time you’ll be exploring the lower dungeon. Any questions? See you in two weeks!” This provides closure and confirms continuation.
Bonus Mistake: Taking Criticism Personally
A player says “That combat felt too long” and you spend the next week feeling like a failure.
Why This Happens
You’ve invested significant effort and emotional energy into DMing. Criticism feels like rejection of that investment. Additionally, new DMs often lack confidence, so any negative feedback confirms fears about inadequacy.
Why It’s a Problem
Defensive reactions shut down helpful feedback. Players stop telling you what isn’t working because they don’t want to hurt your feelings. Problems fester unaddressed.
Taking criticism personally also makes DMing emotionally exhausting. Every session becomes high-stakes performance anxiety rather than collaborative fun.
Exactly How to Fix It
Actively solicit feedback to normalize it: “What worked tonight? What should I do differently?” This frames feedback as expected and helpful rather than criticism.
Separate your worth as a person from your performance as a DM. Bad sessions don’t make you bad. They make you a normal DM who’s still learning.
Treat feedback as data, not judgment. “Combat felt long” is useful information about pacing, not an attack on your competence. Thank players for honesty: “Good to know—I’ll work on combat pacing.”
Remember that players criticize because they care about the game. They want things to improve because they want to keep playing with you. That’s actually encouraging.
The Most Important Fix: Keep Running Games
Every mistake on this list gets better with practice. You’ll over-prepare less as you learn what actually matters. You’ll balance encounters better after seeing dozens of them play out. You’ll create memorable NPCs after watching which ones resonate.
The DMs who improve fastest are those who run games regularly, reflect on what worked, and try different approaches. The DMs who stay stuck are those who either stop running games or run the same way forever without adjustment.
So read this list, internalize the fixes, and then run your next session. You’ll still make mistakes—probably some from this list despite knowing better. That’s fine. Note what happened, think about why, and try something different next time.
Your future self, running smooth sessions for engaged players, will thank your present self for pushing through the awkward early period when everything felt difficult. Every expert DM started exactly where you are now.
The only way forward is through. Your next session is waiting.