In interest of keeping things short though I would just say this:

1) You are young, so young. You are much younger than you think you are. When you hit 56 like me you'll realize that.

2) Keep a positive, problem-solver mindset. In the words (roughly) of Henry Ford "If you think you can, you can. If you think you can't, you can't".

3) Go for a walk daily (30 to 60 minutes) and get 8 hours sleep a night - not negotiable.

4) Keep reading, keep learning.

5) Travel. Pick somewhere that will surprise you and try and live there for a while. I lived in Thailand in 2003 and it changed my life.

6) Worry less. You won't get out alive anyway.

7) Stay frugal (read Your Money or Your Life by Joe Dominguez and Vicki Robin).

8) Watch "The Sunscreen Song - 10 Year Tribute (Everybody's Free)" on YouTube! Great advice!

In many respects my 40s were the best years of my life. Good luck!