At the top of the page, by your name, is a link reading "Account". Click on that, and in the box labelled "Active Profile", choose "Edit Signatures". Ed "My First Signature" and when you're done, set it as default with the radio button, if it's not done automatically for you. (It's been years and at least one ownership change since I last modified my sig, but that should do it for you.)
-- Bob
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Then the horns kicked in...
...and my shoes began to squeak.
-- Bob
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Then the horns kicked in...
...and my shoes began to squeak.