First off, it explains everything in the rules in detail but here is how you create a family-you first need at least three guys in toal with, of course one of you being don. The don contacts a moderator-who are listed in the memberlist. Just say that you want to start a family and he'll explain the rest. If the territory you want is already taken then you must kill the don, and possibly more people to take it over, but being that all the familys are somewhat powerful I highly recomend you don't do that.
And you don't have to put a family or occupation in until you get one.
And whats your name in the game?
*EDIT*
Your profile answered my last question lol