1. Don't get married just because you are in love with the person. "Love" lasts for about... 6 months. Then it's gone. And the daily monotony and routine of life will tear your relationship apart before you know it. Initial love is usually infatuation, and if that's all there really is, the marriage isn't going to last long.
2. Stay positive. I was actually reading through some old blog posts of people I subscribe to on Google Reader (totally recommend by the way), and Don Miller had an interesting post about love. It came from some science magazine, and it said that the key to a successful marriage was staying positive. Now, clearly, you can't save a marriage by simply smiling and claiming everything is alright, but trying to maintain a positive perspective and outlook on life will benefit you, and your spouse.
3. Communication is Key! Just ask Carrie Wiley! :) Communication is vital to any healthy relationship, and especially in marriage. If you don't tell your spouse what you are thinking or feeling, they won't know! Talk it out! Make it work.
4. Keep dating. Don't stop dating your spouse. Just because you're married doesn't mean that you can spend every weekend watching TV and eating take-out. Do things together. Surprise each other.
5. Create a story together. Another lesson from Don Miller. When you are living a great story, you want to keep pursuing it. You want to keep living it. You don't want to leave.
So, bottom line: love is a choice. If you don't choose love, it won't work. And love is worth it. It's worth working at. It's worth choosing.