I am semi-retired. Lord knows I made mistakes along the way. Some advice:
1. Find a good wife. Pretty don't count, what's inside does. If she sticks with you in rough times she's a keeper. Listen to what she says, not just the words. Look at her when she talks to you, turn away from the puter, put down the book. Look at her. Support her interests.
2. Take the time to do the things you enjoy but only when you can. Trust me, short trips can be a lot of fun.
3. Find a group that offers support. Like the Masons. For me it was the Mankind Project. MAKE CONNECTIONS. When you go job hunting it will pay handsomely.
4. Don't burn bridges. If you leave a job or a relationship keep the break clean with no hard feelings.
5. Learn to apologize if you are in the wrong. If it is the wife, apoloqize anyway.
6. Avoid credit debt. It will eat you alive. Trust me, I know.
7. Live within your means. And never buy stuff just to show off.
8. Wait until a product has been on the market for a while before buying it. Let others deal with the bugs and high prices.
9. Enjoy each day like it was your last.
10. Believe and trust in the Lord. Give a prayer of thanks when you are rewarded, too many forget to do that simple thing.