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 profile worksheet. If you want to go deeper with your characters, you'll need a full dossier describing their physical appearance, manner of speaking, behavioral traits, and background. From their hair color to their biggest secret, this questionnaire covers it all.