It's simple enough. First, get in the WoT. Then, submit a deed.

Why is the first step necessary? Because recording something like a marriage contract without also binding it to people, is pointless. That's where the WoT comes in. This would be unprecedented, if you did it. I'm not even sure what the contract should be. Should the groom and father of the bride both sign it? You could use it to publicly declare the dowry or something.