Detail each area/room

Give each area or room a title, something you can refer to in your notes: "Entryway" or "Long hall" or "room A," etc.

Then write out the details and decisions that you want to remember about that area—the stuff you don't want to forget or think through in play. Include some or all of the following:

• A description of the environment
• Impressions from various senses
• Questions you might ask the PCs
• Contents: NPCs, dangers, discoveries, potential events (below)
• Lore, backstory, or explanations
• Exits and connections to other areas

For the contents, include whatever details you need: numbers, where they're found, behaviors, tactics, etc. (see "Make plans" on the next page). For content that has its own stat block or write-up, include a page reference, a copy of that write-up, or a link as appropriate.