Chapter zero
Shape the world.
A few brushstrokes are enough — Muse will build the rest, then drop you into the scene.
Start from a spark
Genre
Tone
Setting
When and where does this take place?
Premise
The hook. What's the situation as the story opens? Who's involved?
You, the protagonist
Name
Pronouns
Who are you?
A few specifics — temperament, history, what you carry into this story.