Here are the steps:
Choose a goal.
When I say teeny, tiny, I’m not kidding.
You want a goal so small that it would actually be more difficult, psychologically, to skip it than it would be to just sit down and do the damn thing.
My go to teeny, tiny writing goal is ten minutes. No matter what, even on my worst day, even when I’m sick, even when I’m travelling, even when I have a million other things to wedge into 24 hours, I write for ten minutes.
If for some reason ten minutes became something I could skip — if it lost it’s status as the goal that’s so small I’d rather do it than skip it — I’d shrink it.
Hell, one word. Seriously. If that’s what it takes, set a goal of writing one new word on your manuscript everyday.
The secret of the teeny, tiny goal is that it’s not the finish of it that matters. It’s the start. The magic is in the way that little bitty goal gets you from NOT writing to writing.