Professor 3's advice:
Get tough deadlines. That forces you to work.
He has have tried to concentrate his teaching to limited periods, and that has sometimes worked.
Write with others! Be part of a project, and team up for writing. It's a tremendous help.
Professor 3 keeps a five-year plan of everything he intends to do: what papers and books (yes, he writes books at the speed many others write papers) that are to be finished when. He showed the plan to me: it was a list on a piece of paper, written with a pen. Half of the items were crossed out.
Then it's just to start working!