How to Live Life Like a Barber (Ten Simple Rules)

1. Maintain a good posture.
2. Wear an easy cheerful countenance.
3. Constantly practice friendliness.
4. Speak distinctly.
5. Don't be overly inclined to give advice.
6. Don't be didactic.
7. Be a good listener. A good listener asks leading questions.
8. Be essentially informal.
9. One's success in any avenue of life depends a great deal upon his selling ability.
10. Don't take yourself too seriously.

Found on page 32 of Schulz and Peanuts: A Biography by David Michaelis. Originally printed in The Art and Science of Barbering.

According to Michaelis, these principles "established the professional tactics of Charles Schulz's entire career". They seem like good principles to practice, even if I'm not a barber or one of the world's greatest cartoonists.