First sign in. Then User CP (on the left in horizontal menu near the top). Then within User Control Panel (on the left, a vertical menu) Edit Signature.
On edit: Tex1961, you beat me to it..
There's lots of advice and information in forums... sometimes it is correct. For example, all of my posts are made by a political appointee who got the job as a reward for contributions to my diesel bill.
2011 Jayco 28.5RLS; 2008 Chevy Duramax; Pullrite Superglide Hitch