I don't begin until I have an idea. But this idea is more than just a glimmer, more than a potentially evanescent wisp of inspiration. For me, what the idea is is a complete thought that contains one of three elements:
- The primary event that will get the ball rolling in the novel
- The arc of the story containing the beginning, the middle, and the ending OR (and please note that word OR)
- An intriguing situation that immediately suggest a cast of characters in conflict.
If I have one of those three elements, I have enough to begin.
[Note from me: Item #1 up there is, in scriptwriting parlance, the catalyst of the story. In children's books, that catalyst should be as close to the beginning as possible and, ideally, clearly identifiable. The reader jabs a finger onto the page and says, "Here. This is where the story starts."