You do it before you have a chance to think twice. Before the little voice says your knees hurt or suggests that an hour on exercycle with the latest issue of People would be just as good.
Now I'm finding out that writing is like that, too. It seems like my best writing comes before noon, and that if I really want to get a lot done, I should write before I eat. [Full disclosure: I'm not stupid enough to try it before coffee.]
Right now, everything is colliding. But I think writing is going to have to come first. I have to be productive. I have to write 15,000 words or so by Feb. 29.
So it's off to my laptop and breakfast can wait.
What works best for you if you want to be productive?