71-year-old shares the 22 'most useful' life lessons for young people—'how much to tip' and handling 'rude people'

A few years ago, I decided to write down bits of advice I wish I knew earlier in life, and then share them with my adult children. To my surprise, I had more to say than I thought.

At 71 years old, I've accomplished a lot. I helped launch a magazine and wrote a bestselling book on the technological forces that will shape our future. I've given talks on how to remain optimistic during challenging times.

My goal is to channel the wisdom of the ages. Here are the most useful life lessons I think all young people should know:

1. How to talk to people: Listening is a superpower. When talking to someone you love, keep asking them, "Is there more?" (until there is no more).

2. How to learn from people: If you're the smartest person in the room, you're in the wrong room. Hang out with, and learn from, people smarter than yourself. Even better, find smart folks who will disagree with you.

3. How to be interesting: The more you are interested in others, the more interesting they'll find you.

4. How to save money: Live as cheaply as you can when you're young, for at least six months. Own as little as possible. Live in a tiny room — and eat beans and rice. This way, any time you have to risk something in the future, you won't be afraid of the worst-case scenario.

5. How to earn respect: Be honest about your faults. Nothing elevates a person higher than taking responsibility.

6. How to handle rude people: Treat their behavior like an affliction or illness they have. This will make it easier to have empathy towards them, which can soften the conflict.

7. How to find your passion: The best way to start is to be an expert on one thing. Through mastery, you'll command a viewpoint to steadily find where your bliss is.

8. How to raise confident kids: Reinforce their sense of belonging to a family. Articulate exactly what is distinctive about your family. Your kids should be able to proudly say, "Our family does [X]."

9. How to raise smart kids: When they ask an endless string of "Why?" questions, don't answer all of them. The smartest reply is, "I don't know. What do you think?"

10. How to buy and sell stock: If you are buying stock, the person selling it thinks it's worth less than you do. If you're selling, they think it's worth more than you do. Each time you're ready to buy or sell stock, ask yourself, "What do I know that they don't?"

11. How to spend wisely: Select a few interests that you can gleefully splurge on. In fact, be all-around thrifty so that you can splurge on your passions.

12. How much to tip: As long as the experience was pleasant, always tip at least between 15% and 20%. And if you stop to listen to a musician for more than a minute, you owe them a dollar.

13. How to be resilient: There are three things you need in life: the ability to not give up on something until it works; the ability to give up on something that doesn't work; and the trust in other people to help you distinguish between the two.

14. How to boost your salary: The best time to negotiate a salary for a new job is the moment they say they want you, and not before. Then it becomes a game of chicken for each side to name an amount first, but it is to your advantage to get them to give a number before you do.

15. How to identify imposter syndrome: When you create things that only you with your unique talents and experiences can do, then you are absolutely not an imposter. You are the ordained. It is your destiny to work on things that only you can do.

16. How to be happy: Unhappiness comes from wanting what other people have. Happiness comes from wanting what you already have.

17. How to get better at public speaking: Watch a recording of yourself speaking. It will be shocking and painful, but it's the best way to improve.

18. How to give a proper apology: Express genuine empathy with the other person, take responsibility, and offer a remedy to fix things.

19. How to ask stupid questions: Just do it. Ninety-nine percent of the time, everyone else is thinking the same question and is too embarrassed to ask.

20. How to make good decisions: Ask yourself, "Which choice will pay off now more than later?" The easy choice pays off right away, but the best choice will pay off at the end.

21. How to measure wealth: It's not by the things you can buy, but by the things that no money can buy.

22. How to pick the right advice: Advice like these are not laws — they are simply hats! If one doesn't fit, try another.

Kevin Kelly helped launch and edit Wired magazine. He has written for The New York Times and The Wall Street Journal, and is the author of "Excellent Advice for Living: Wisdom I Wish I'd Known Earlier" and "What Technology Wants, and The Inevitable." He frequently gives presentations about the consequences of technology.

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