I'm a newbie

Hey, I made this profile before but I barely started using it now.
I have a website of my own, I'm also on Quizilla, YouTube, MySpace, Yahoo, and now on here.
I've always wanted to see how this site works so here I am.
If anybody can or wants to, can you help me with my profile? Like how to add the layout and background.
I'm good with computers but I don't get how to do it. I know how to on MySpace and youtube but not on here.
So if anyone belives taht chivalry isn't dead, can you help me with my profile and how this webstie works?
Thanks.