I've discovered something about myself--something I could have done with discovering a few decades ago.
I work best when I use a timer. I have become a devotee of Pomodoro intervals: twenty five minutes of work, followed by five (OK, usually a bit more) minutes of break. Pomodoro Technique has a lot more to it, but I'm not really that strict about it.
But when I time, I work. That doesn't mean I literally don't work when I'm not timing, but the odds definitely go way down. I often delude myself that I'm working only to conclude, on mature consideration, that I'm not. Because the damn timer's not on.
Those twenty-five minute intervals are perfect for me. I work intensely, but that is about the time my mind would start to wander. So I get an official break. I generally follow the rule of sets of four (two hours), with a longer relax in between. If I do it strictly, without cheating, I get an immense amount done.
I often fail. But more and more often, I succeed. My mind is astonishingly disordered. I need external rules to get anything done. I'm fortunate I can dress myself. I am a triumph of technique over essential personality.
But now I am off the timer and should finish. The more strictly I obey the breaks, as well as the work periods, the more I get done. So now I'm done!