Snowflake method checklist. Maybe you'd rather work from the top down than from the ground up. Inspired by fractal geometry (really!), Randy Ingermanson's "snowflake method" grows an entire novel from a single sentence. Each step of the process methodically expands upon the one before, filling in detail until you have a complete draft.
Character biography. Now that you know who's who, here's a template for figuring out how they got to the situation in your novel. When it's time to write a flashback or refer to a past event, you'll breathe easier (and save yourself some edits) knowing you can look up the dates in this simple timeline.