Things are just popping up in my head these days. While I've been finishing the latest draft of one story, ideas for others have been slipping in and saying "Hey, when you're done with that one, what about this?"
These ideas are just nuggets, not fully-formed plots or anything. Just a snippet of "what about" mixed with "then what if" and tossed with "what next". What happens with them is that they go into a notebook I've been keeping for a little over a year. It's a spiral notebook that I take with me to the day job so that if something pops up, I can write everything I know about it at the time and forget it.
That's right, forget it.
Since I'm not a full-time writer I haven't yet been able to juggle multiple projects. I think I know how to do it, but I'm already juggling the full-time day job (which is what pays the bills and buys the whiskey) and the writing (which isn't paying anything except in experience and contacts). Oh, yeah, I have a family, too. Subdividing the writing isn't in my best interests at the moment, so I have to write down ideas and let them marinate when I go back to the immediate work at hand. This means I'm probably one of the slowest writers around.
That said, when I was just writing The Long Range I was able think two or three stories ahead because they were all interconnected. Plus they were just for me, so I was the only person I had to please. This last story took me way longer than I wanted it to, but I wasn't writing it for me. I had to give it as much focus as I could. It's a job and that means I had to do it as well as I was able.
So when I get an idea while I'm writing those projects for others (and I'm excited to do them!) I have to let it sit. When I get back to them, like I have today, I read it over and ask myself if it still appeals to me. If it doesn't, then I move on to another. If I like an idea I start looking for an angle that I hadn't seen before, if none comes I move on to the next one and so forth and so on.
I look to see if I can combine ideas, too. Sometimes I'll scratch one idea off and add it to another with a note of where it came from. Then I close the notebook and forget it for the time being. The notebook is a mess to look at and has pieces of paper paperclipped and stapled to it, various colors of sticky notes in there, too.
It takes a longer time to decide which of those ideas I'd like to explore further in a story.
Unless of course I get excited about something and start pounding away at the keyboard. But that's another process.