Make a list of B-Roll and direct cinema footage that you want in the film. This can be a list of photos and documents as well as video footage you will need to get when in production. All events, locations, people, and important images need to be represented or re-created so you will need to know what you want and how you will be able to get it. Make lists of the exact types of shots you want to get, and how much direct cinema footage you would like. Also identify the difficult footage to get access to and try and identify possible alternatives that could take its place.