The instructions apply to Mac OS X 10.4 (Tiger) and later.
The keyboard shortcut isCommand+,(comma).
Highlight the signature you want to edit.
Make sureRich Textis selected underMessage Formatfor formatting to be applied to signatures.
For more advanced formatting, compose the signature in anHTML editorand save it as a web page.
bring up the page in Safari, highlight all and copy.
Finally, paste into a new signature in Mail.
This will not include images, which you’re able to add using the above method.
