Creating and maintaining your personal toolbox for efficient session planning.
November 26, 2025
Every few weeks I see a post like this:
“After years of DMing, I still feel like I'm wasting hours each week with session prep.”
Or:
“My players never go where I prep. I spend all Sunday on stuff they never see.”
When I started running long campaigns, I treated every session like a miniature adventure module. I’d sit down and try to write this week’s content: locations, NPCs, encounters, beats. If the players followed the path I’d sketched, it was glorious. If they decided to go visit the blacksmith three towns over instead, 80% of my work went straight into the void. I think I likely got the idea from pre-written modules, which have a whole bunch of crafted content along some kind of pre-determined path.
That's great for people who write modules, because many people are going to use them, and different groups will follow different paths, so nothing will be wasted. But I only have one group! They are absolutely not going to follow the narrow path, and I wouldn't really want them to. On the other hand, I can't just not prepare content. Improvisation works great in bursts, but over a long campaign it becomes harder to maintain consistency, payoff, and depth.
What I've settled on instead is to separate prep into two parts: there's an expanding set of content that is "the campaign" as it actually exists - lore, locations, NPCs, etc - and then there is the "play material" - a kind of consumable resource that I spend as freely as I want. Secrets, scenes, encounters, items and anything else that might become part of the campaign if it comes up at the table.
In another post, I broke down my session prep into a seven-step cycle. That workflow helped, but there was still a nagging friction: I was doing too much from scratch. Each Tuesday felt like reinventing the wheel. New scenes, new locations, new NPCs. If the party zigged where I expected them to zag, that work simply evaporated.
Eventually, I noticed the pattern:
It's kind of an unpleasant grind, and it tends to push me into railroading the table into a path that uses that content. My mistake was thinking of prep as “writing this week’s content.” Efficient GMs think of it as “assembling a toolkit for the week.”
It changes week to week, but a lot of that toolkit isn't consumed in a single session. Ideally your workflow accounts for that, so that you can easily find and reuse the things that you've already prepared and mark off the things you already used.
If you’ve worked in software, "backlog" sounds like a list of tickets. That’s not what I mean.
A GM backlog is just a curated library of things the game can throw at the party. I call it play material. It’s made up of small, reusable pieces that aren’t tied to a single session or a single path. Critically, they're not nailed down to a specific place or time. They don't actually exist in the world yet, because you haven't used them.
For example:
When you have a backlog, Tuesday's prep scramble changes. There's still writing, creating, and refining, but you're starting from a library of things that you've already prepared.
I start by skimming the last session’s notes. What are the party’s goals? What’s hanging over their heads? Where are they standing?
Then I open the backlog and scan. The secrets from last session form the basis of the next quest steps, and the secrets they haven't found yet are still out there - or maybe not, maybe some of them have resolved themselves.
I pick a couple of problems to push, two or three NPCs to feature, and a few scenes that fit the mood. Then I stitch them together into a loose outline: a strong start, a few likely beats, and the secrets that might surface.
The new writing goes into the most important places: the campaign arc, what is happening out of sight, and the secrets that might surface. And when the party wanders off for a shopping episode, which they will, then it's easy to pull in plot threads when the time is right.
Unused prep doesn't go in the bin. It goes back in the inventory.
Two things kill a backlog: starvation and rot.
Don't let it starve. After each session, add 1–3 things. Did you improvise a fun goblin? Add him. Did they mention a "Tower of Silence"? Create a stub for it. Did they make an enemy? Write down the Front.
Don't let it rot. Occasionally prune. Merge duplicate ideas. Archive the stuff that doesn't fit anymore.
You aren't building a wiki; you're keeping a toolbox. If a tool is broken or rusty, throw it out.
In my opinion, but this is exactly where AI tools belong: not running the game, but managing the library.
An assistant is great at two things here: Recall ("Find me that NPC I improvised three sessions ago") and Cleanup ("Turn these messy session notes into a clean NPC entry and a new Front").
That’s the philosophy behind Campaign Arks. We call this library Play Material, but it's just a backlog. The AI isn't there to write your story; it's there to help you find, connect, and reuse the work you've already done.
If prep has started to feel like homework, it’s probably because you’re still treating every week like a brand new project. You don’t have to fix that overnight. Just start noticing what you’re already making that could live longer than one Tuesday.
When something works at the table, don’t let it vanish into last week’s notes. Throw it in the backlog. When something never comes up, don’t feel bad about it—cross it off, or let it sit on the shelf until the campaign wanders its way back around.