How do you keep yourself disciplined?

I find the 10 rules by Napoleon Hill a classic, but still valid list. It works for every aspect in life,
especially when dealing with executives, producers, actors, etc.

1. Keep your cool even when the other person isn’t
2. There are 3 sides to every argument: your side, the other person’s side, and the right side
3. Never give a directive to a subordinate when angry
4. Treat everyone as though they are a rich relative whom you want to remember you in their will
5. Look for the seed of equivalent benefit in every negative situation
6. Ask questions then listen to the answers
7. Never say or do anything towards another without first asking yourself this question: will it benefit them or hurt them?
8. Learn the difference between friendly analysis and unfriendly criticism
9. A good leader is one who can take orders as cheerfully as they give them
10. Tolerance in human relations is of vital importance

More Info: Napoleon_Hill
Image: Public Domain