Well, if you haven't found the answer yet, you need to talk to Maramal in Riften. He is the head priest of the temple of Mara. Ask him about marriage and how it works, then buy an Amulet of Mara from him. Once you do favors for certain people, some of them will be available to marry. Look this up on Google to see which people you can marry and which you cannot. When you find out who is available and who you want to marry simply put the amulet of Mara on and ask if they're interested. From there, everything is pretty much objective.