Have Writing Goals.
I know this sounds like duh but then there's the second part.
Publish your goals for the world to see.
And since I'm a lead by example kinda writer
Here are my writing goals for February and March. You can also check my book "Writing Goals" to get an idea of how much I'll be writing any given day. Though I sometimes don't complete my goals as those of you who read my book know.
But be harsh on me when I don't I need motivation!