User blog:GuacamoleCCXR/How do you do those backgrounds on the userpages and stuff?!?

I noticed that most people have such awesome backgrounds and text colors on their user pages (User:1999Bug, User:Legobatmankid10 and many more), so how do I make one? I checked the source of Bug's page, but it didn't really help me (I found the code, but it was just a lot of names of colors and such stuff, I couldn't really find the code for the background), so could anyone please tell me? Thanks.