They say hindsight is 20-20. Here is an article on the things this man wishes he could have known better when creating his foundation for adulthood. Figured there might be some helpful reminders for us all! (He elaborates on each item in the article.)
20 Things I Wish I Had Known When Starting Out In Life

1. How to control impulse spending.
   
2. You gotta stay active.
   
3. How to plan finances.
   
4. Junk food will come back to bite you in the butt.
   
5. Smoking is just dumb.
   
6. Fund your retirement, son. And don’t withdraw it.
7. All the stuff you’re doing that seems hard — it will be of use.
   
8. Don’t buy that used van without checking it out closely.
   
9. That guy you’re going to sell your car to? On a gentleman’s agreement? He’s not gonna pay you.
10. Make time to pursue your passion, no matter how busy you are.
11. All that stuff that’s stressing you out — it won’t matter in 5 years, let alone 15.
12. The people you make friends with are so much more important than your job or the things you buy.
13. All that time you spend watching TV is a huge, huge waste of time.
    
14. Your kids are going to grow up way faster than you think. Don’t waste a minute.
15. Forget the drama. Focus on being happy.
16. Pay more attention to blogs when you first hear about them. They’re more than just journals.
17. Speaking of which, keep a journal. Seriously. Your memory is extremely faulty.
18. Tequila is seriously evil
19. Yes, you can do a marathon. Don’t put this goal off — it’s extremely rewarding.
20. All these mistakes you’re going to make, despite this advice? They’re worth it.