I recently watched a video of Stephen King talking to a group of university students. It was a question and answer type of thing, and at one point, the subject of keeping a notebook of ideas came up.
If I’m remembering this correctly (and in the spirit of full disclosure, it’s completely possible I’m not), King said he didn’t have one. He took a survival-of-the-fittest approach when it came to his ideas. If something occurred to him that sounded like a decent story idea, he’d let it rattle around in his head for a while, along with whatever else was in there at the time.
If the idea was persistent enough and kept presenting itself, he’d eventually get around to writing it. It was his way of letting the cream rise to the top.
At this point, I’m going to state the obvious: I am not Stephen King . . . yet. (But I’m comin’ for you, old man. You best be keepin’ a lookout.)