Yes, I’m still doing this : ). I bet you were lost without it. Anyway, a while back I stumbled across this gem by Storyfix.com.
Basically, it’s a list of questions you should be able to answer by the time your book is complete. Note: not your first draft, not your fifth, not your fiftieth; when it is COMPLETE. Between each draft, you should be able to answer more of the questions. Just keep in mind that you shouldn't try answering all of them in one draft.
There’s not much else for me to say. The post really speaks for itself. I strongly advise you to bookmark it and periodically check it against your story, whether you’re in the writing or editing phase.
Now if you’ll excuse me, I have some questions to answer…