This works for me. It may (or may not) work for you, depending on whether you're a planner or a seat of the pants writer:
When I'm beginning a book, after writing the synopsis, I compose a very brief list of scenes. Just a one to three or four-line description of what is happening in each scene, what the point of the scene is and what important points (backstory, emotional, whatever) will be revealed during that scene. When I sit down to begin writing, all I need to do is reread yesterday's pages and look at the scene description of what I plan to write today and I'm off and running. (Note: I don't force myself to stick to the plan if something better comes along, but it's good to know that I do have a workable plan).