Howdy and welcome; enjoy your stay.
Say again? Do you mean characters in the role play forums? My understanding is you just write up a profile for your character (a brief physical description, some background, etc.) by way of introduction so folks know how to relate to you. Just make sure the one you're joining isn't overloaded with "a cast of thousands." Of course, I'm not a roleplayer, but it seems from the outside like that's all there is to it. I'm sure no one there would object to one quick O(ut) O(f) C(haracter) post to ask for a PM with instructions of something. If you're talking about some other form of role play, like pen and paper or online, well, that would depend on the game.
Anything else with which a fellow newbie can help?