One-hour prep for a TTRPG session

A TTRPG session prep routine that fits inside one hour beats an open-ended one, because prep expands to fill whatever time you give it and most of what it expands into never reaches the table. The hour splits into four blocks of ten to twenty minutes and holds up across systems, from dungeon crawls to horror one-shots.

Minute 0 to 10: read your own notes backward

Start from what happened last session, especially the loose threads players pulled: the NPC they liked, the door they did not open, the promise they made. Write down three of those threads. Player-created threads beat prepared plot because the table is already invested in them; your job is mostly to pay them off. This is where campaign notes earn their keep, and why writing two lines after each session saves twenty minutes before the next.

If you have no notes because last session ran late and you went straight to bed, read the group chat instead. What the players joked about afterwards is a reliable index of what landed.

Minute 10 to 30: prepare situations, and let scenes emerge

For each thread, sketch a situation in three parts: who wants what, what stands in the way, what happens if the players never show up. Skip scripting outcomes entirely. A situation survives contact with players because it has no required path; a scripted scene shatters the moment someone casts the wrong spell at it.

Mike Shea's eight steps of Lazy D&D game prep work the same way. The list runs from reviewing the characters and writing a strong start through outlining potential scenes and defining secrets and clues, and the scene outline is deliberately small, a few short sentences in a list. Secrets and clues are written so they are not tied to where they get discovered, which is what lets you hand one over wherever the players happen to look.

Two or three situations fill a session reliably, because players expand everything. Prepare a fourth only if the group is large or the players tend to blow through material.

Minute 30 to 45: stat the moving parts

Now, and only now, numbers: the NPCs likely to matter, one fight worth having, one location worth a map sketch. Steal shamelessly from your system's published material; reskinned stat blocks are indistinguishable from bespoke ones at the table. The per-system GM prep checklists cover what this step means in your game, whether that is encounter design or a Call of Cthulhu clue chain, where the first-time Keeper guide goes deeper.

One fight is usually the right number. A second prepared combat is the piece of prep most likely to go unused, because a fight that matters takes longer than anyone plans for.

Minute 45 to 60: build your one-page screen

Condense everything onto a single page you can see at a glance: names (a dozen spares, because players will talk to the fishmonger), the three situations, the stat references, and your opening line. A strong opening line, prepared word for word, is the cheapest quality upgrade in GMing; it launches the session while everyone else is still finding pencils. Keep NPCs and hooks in the NPC toolkit.

Leave a blank strip down one side of the page for what happens during play. Names the players invent, promises you make on the fly and the thing you said an NPC knows all belong there, and that strip is what makes next week's first ten minutes work.

The fifteen-minute version

Some weeks the hour does not exist. Cut in this order: the map sketch, then the second NPC, then the stat blocks, which you can improvise from any similar creature. What survives to the end is the three threads and the opening line, and a session run on those alone is noticeably better than one run on a fully statted encounter with no idea what anybody wants.

The discipline part

The hour works only if you protect it from the fun kind of prep, worldbuilding, which is a hobby in its own right and belongs outside the hour. If a detail cannot come up in the next four hours of play, it goes in the campaign wiki instead of the screen.

Prep the parts the players will touch.