Marriage Starter's Guide
1. To get married, you'll first need the Amulet of Mara. While wearing this jewelry, you will unlock new dialogue options with certain NPCs.
2. Buy the amulet from Maramal, sold for 200 coins. Maramal can be found in Riften, either in the Temple of Mara or in the Bee and Barb.
*The amulet can also be found in a chest at the beginning of Bleak Falls Barrow — a main quest.
3. To get married, you must first speak with an NPC and talk to them about marriage. They might accept, or require a small quest to be completed. If your Speech skill is high, you can attempt to raise their disposition to you, or bribe them.
4. If they do accept, speak to Maramal at the Temple of Mara to plan the wedding.
A married NPC will move into whatever house you own and provide several benefits.
Your spouse will cook one meal a day, which raises your health and stamina. Your spouse will also follow you as a companion if requested, defending you or attacking enemies on your orders. They will also carry some of your equipment for you. Spouses will sometimes give you gifts.
Now that you're married, you should probably be looking for a house to buy. You might also want to look into curing that whole werewolf thing. On second thought, you might want to cure that beforehand.