up top where it says welcome back Alexian there is a USER CP link,
this is your control panel
choose the option to change signature
you'll need to have your photo's web address( where it's at on the web)
there's some free sites for easy uploading like photobucket.com etc...
you can use the [img] tag and put the
http://www.your pic address goes here. com followed by the closing img tag [/img]
or you can do the <img src tags if you know html.
if this is all greek to you, email me at randyp(at)myactv(dot)net with the picture you want in there and i'll fix you up.