1. Speak as little as possible about yourself.
2. Keep busy with your own affairs and not those of others.
3. Avoid curiosity.
4. Do not interfere in the affairs of others.
5. Accept small irritations with good humor.
6. Do not dwell on the faults of others.
7. Accept censures even if unmerited.
8. Give in to the will of others.
9. Accept insults and injuries.
10. Accept contempt, being forgotten and disregarded.
11. Be courteous and delicate even when provoked by someone.
12. Do not seek to be admired and loved.
13. Do not protect yourself behind your own dignity.
14. Give in, in discussions, even when you are right.
15. Choose always the more difficult task.
h/t Young Fogeys