I'm currently out at one of my favourite places for the start of our week-long winter writing retreat. I'm continuing work on the first draft of my latest novel, trying to stop myself thinking about whether the story is any good. I'm just about halfway through at this point and my aim is simply to push ahead, adding new scenes to edit later.
In writing each one, my attitude is to 'throw everything I can at the page and sort it out later'. I simply write down, as basically and ineptly as it comes out, everything I can think of that might need to be in that scene. Then I let it sit for a bit, usually until the next day, come back and tinker with it, moving things around, cutting bits, adding bits, and editing to the point it reads logically if not brilliantly.
It's like throwing handfuls of paint at a canvas and coming back to refine the picture later. Maybe the act of throwing everything out there first lets me get a handle on all I have or need to work with and during the break my subconscious sorts it all out for me.
In any case, it seems to be working. With a first draft, progress is the only requirement.