GM Guide

Session Prep in 15 Minutes: A GM's Guide

7 min read·Published April 17, 2026

The Over-Prep Trap

Here's a stat that should make you reconsider your prep routine: GMs spend an average of 6 hours preparing for every 1 hour of play. That's a 6:1 ratio. For a hobby.

And here's the cruel part — most of that prep never gets used. Players ignore the dungeon you mapped. They befriend the villain. They spend two hours talking to a shopkeeper you invented on the spot.

The solution isn't no prep. It's the right prep. Fifteen minutes of focused preparation will serve you better than three hours of world-building your players will never see.

The 15-Minute Framework

Set a timer. Seriously. Here's what you prep in those 15 minutes:

Minutes 1-3: Review — What happened last session? Read your notes (you do take notes, right?). What did the players say they wanted to do next? What loose threads are dangling?

Minutes 4-8: Three Scenes — Not a plot. Not a story arc. Three scenes. Prep a location, a situation, and one NPC per scene. That's 9 total elements.

Minutes 9-12: NPCs — For each scene, write one NPC with a Want and a Secret (see our NPC creation guide). Three NPCs, two lines each. Done.

Minutes 13-15: Bangs — Write three "bangs" — dramatic moments you can deploy if the session stalls. A messenger arrives with bad news. An explosion in the distance. A betrayal revealed. You probably won't use all three, but having them means you're never stuck.

What You Should Never Prep

Some things are a waste of your prep time. Cut them:

The Session Notes Hack

The single best thing you can do for your next session is take notes during this one. Specifically:

Five bullet points after each session. That's 2 minutes of work that saves you hours of prep next week.

Random Tables Are Your Best Friend

When players go off-script (and they will), you need to improvise. Random tables make improvisation feel prepared:

These tables aren't prep for a specific session — they're prep for every session. Build them once, use them all campaign.

Automate What You Can

The parts of session prep that take the longest are the parts that don't require creativity: generating NPC names, writing location descriptions, creating encounter outlines, and making sure everything is consistent with your existing world.

Lorewright's Session Planner does exactly this. Select 2-5 elements from your world — a faction, a location, a couple of NPCs — and it generates session notes with encounter outlines, NPC dialogue hooks, and scene descriptions that are consistent with your existing lore.

That's not replacing your creativity. That's automating the busywork so you can spend your 15 minutes on the parts that matter: deciding what happens next, what choices to present, and what surprises to spring.

Your World Is Waiting

Stop prepping. Start creating. Lorewright builds the world — you bring the adventure.

Try the Session Planner Free → See a Demo World