I am assuming that you already know how to RP.
First things first, get a skin that will fit the description of your character by entering one of those stores called "Local's Only."
The only thing you can do after that is to start RPing with other people, earn money through sidejobs and eventually join a faction.
Here's a wonderful guide by Mr. Dodds on how to make money on the server -- if you're keen on earning money early,
I suggest you read this. viewtopic.php?f=4&t=28573