From a father/husband...in no particular order...
1. It's not about you. You should always come last after the wife and kids.
2. If she's not good enough to be your best friend, she's not good enough to be your wife.
3. When you have kids, think back to when you were a teen, and remember the troubles you and/or your friends had with their parents. Don't be one of those parents...do it right!
4. Have lots of chickens, and enjoy them together.
5. Definitely have kids. Adopt or have them...the other way, but definitely have kids...unless you hate kids, then DON'T have kids.
6. DON'T LET "MODERN" SOCIETY'S NORMS TRICK YOUR BETTER JUDGEMENT OF WHAT'S RIGHT AND WHAT'S WRONG. This goes for your relationship with your spouse AND the way you raise your kids.
7. If you're a father/husband, your #1 job is to protect. If you're a wife/mother, your #1 job is to nurture.
8. Don't move too far away from your family...unless they're psychotic. Then move very, very far away.
9. Get to know your neighbors...unless they're psychotic. Then stay very, very far away.
10. Nurture the individuals within each of you as well as the couple you've become. Give each other enough space, or "territory" so that you can keep your own identity. For instance, I give my wife 100% reign over the inside of the house. She gives me 100% reign over the outside. I can plant whatever I want in the yard, and she can put up whatever kinds of curtains she wants. Everyone's happy.
11. Don't stop dating...each other that is. After you've been married for 20 years, you should still go out on dates--that means without kids.
12. Remember in 20 years how you laughed together when you were engaged.
13. Be flexible. Change is inevitable, and both people in a marriage will change over the years. Stay close, and the changes will parallel. Drift, and the changes will pull you apart.
14. Did I mention get lots of chickens?