You mean a signature (or siggy for short)? All you have to do is apply an image to your signature box on the user control panel. If you want a banner though you have to make one or get someone to make on for you.
Your sig is waaaaaaaay over the limits in pixel height. Like, this much too high *Points at Empire State Building*. Better shorten it before Alcar sees.
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Fuzzle Guy: Apart from going swimming I've never been more wet in my life than when I went to see Take That.