The only thing we ask about sigs is you limit them to a reasonable size. Its not a hard-assed rule, but more of a request.
(some people use big banner sigs, we simply ask you keep it to text, url's or a small strip of graphics)
Most of the controls are super-easy.. however, the recent forum rebuild has a couple buggy flaws in it. Like, your avatar may disappear or fail to upload.
You have two other places where you could personalize your profile: Personal text, and personal title. Those will appear above and below of your avatar.
Don't be shy, any mods are here to help. We don't always respond immediately, but we'll respond. Just look for the blue stars, click their name, and send a Personal Message. Thats what it's there for.