There are four basic questions to ask yourself when you have a story idea to develop, or whether you should let it remain in your notebook to mature a while longer.
1. Is it your story to tell? Is this something I really care about, something I partly understand, something that seems to want to be worked out?
2. Is it too personal for readers to become involved with? Can I work with this idea in a caring but uncompromising way to make it meaningful to someone else?
3. Is it going somewhere? Can I dramatize this in a series of scenes with a minimum of explanation? Does it have a plot or can I create a plot for it?
4. What's at stake? Is there something quite specific and vital at stake - not just to me, but to one or more of the characters involved?
If you test your ideas against these four criteria, a lot will be tossed out, or saved in your notebook for later. Don't let that upset you. There are a lot more where that came from and some will pass the test with bells ringing and flags flying. All you need is one good idea to create a solid story that keeps you writing productively for quite some time. Good luck!