Notes and reminders for typical story elements
basicly as a bit of a helpful guide, things like, plot point 1, 2, climax notes
Sections for character information, possibly set out like a facebook page, with sections for their role in the story (protagonist, antagonist, friend, guide etc.) motivation, background, age, etc. these are the sort of things that would make creating fully formed characters easier for me. The information for the whole story could be similar, with a box labelled dramatic question, inciting incident.
I know it is all terribly cliched but it would all help me form a complete story