To edit your signature, you'll need to have posted 20 times and been part of the site for 20 days. (Frustrating, but it does help prevent spam.) After that, the option to "edit signature" will appear in your quick links menu and in your user control panel. Once you've gotten to that point, all you have to do is go to
tickerfactory.com and make the ticker, which you can then paste the code for into your signature.