I gave my kids some rules for life -- not exactly golden but highly practical.
1. Never change a tire on the side of the road. The tire is already bad so roll with it to a safe spot.
2. Never trust a secretary or school administrator to deliver a paper or document. They get dozens of them and generally don't care.
3. Never lend you wallet, your watch, or your wife. My high school gym teacher once sat us down for rules of life and this was one of the -- still not sure what he meant.
4. Walk away from a broken bottle fight or a fight with guy who really knows karate -- no one will ever call you a chicken [also from my gym teacher].
5. Never lie to your doctor or your accountant.
6. If someone starts to show their gun collection at a party, just leave. That's how tragic accidents happen.
7. Don't try to be friends with friends or family -- set the rules, establish a business/working relationship, and enforce it. Then you can be friends.
8. Use the right tool for the job.