1) When you argue, stand/sit next to each other instead of across from each other. This gives a subtle reminder that you're still on the same team instead of opposing teams.

2) Tell them DAILY that you are GRATEFUL for them and what they do. Not just "thanks for loading the dishwasher." Instead, say "I am grateful for how you keep our kitchen clean." "Thank you" becomes trite if you use it too much... which you should. Saying you are "grateful" means a lot more.

3) If you fight about money, it isn't about money, it's about power. Keep that in mind when you're arguing about money. It's a power struggle that REALLY needs to be resolved if your marriage is going to last.

4) Don't bicker about stupid shit. Find a solution together. I learned this one from my wife early in our marriage. She had a habit of leaving soap on the kitchen sponge when she finished cleaning. I got all pissy about having to rinse off the soap every time I used the sponge. I focused on what a pain in the ass it was to rinse the sponge and she just put out a second sponge that she did not put soap on. She focused on the solution while I focused on being butt hurt. It's a lesson I will never forget.

and

5) Husbands- send your mother-in-law flowers on your wife's birthday with a thank you card.