I'm technically a first draft in my head writer, since I like picturing things in my head first as I fall asleep/shower/travel in the bus. It works well for fic of a few thousand words, but when I started hitting novel length I get confused. Yes, this scene is cool, but it doesn't mesh with this other scene! And how do they both get to the thing 10000 words in the future?

I tried to plan it out, but then when I sat down and started writing the thing would always "derail" because it didn't feel right. So now I write the first thousand words I can see and then play the rest by ear. It's a bit like driving with the end destination in mind, but only figuring out the route as far as I can see XD