Go on Paint or Photoshop whatever you use, draw a picture then save it in PNG format.
Upload it to www.tinypic.com and then put it in your signiture area. My controls then edit my signiture. Then just copy the URL for the image you uploaded in there includin the image things so it should look like this:
CODE
[img]www.tinypic.com/*[/img]
Except it will be your link and without the *.
You're done

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