I read somewhere that he had some kind of hysterical speech impediment and that he trained himself out of it by rhyming or singing until he could speak normally.

There's also his method where he writes down his goals 15 times a day until you reach that goal. It sound silly, but it worked really well to keep me focused. I took it kinda to the extreme, and used it as a springboard to maintain other commitments to achieve my goals too: jog 3x a week, not eat chocolate, no coffee, no masturbating, no TV, and no music. I would also write out my goals taking only 15 breaths and not blinking for extra brownie points.

I did this in the 5 months before my exams, all the way until I would get my grades. High school and Uni -- almost a decade where I would just go on full discipline mode for several months.

I don't do it much now, except when I had a health scare last year and what got me back into shape? You bet it was that method.