Creating HTML Mail Signature in Mail App for Mountain Lion (OS 10.8 and Mail v6)

It was a little ridiculous how difficult it was to figure this out but after a bunch of searches here’s the best thing.

  1. Design an HTML signature in some HTML editor.  Save that file as “Signature.html”.
  2. Open “Signature.html” in a text editor.  Copy the HTML to the clipboard
  3. In “Mail” open “Preferences -> Signatures”
  4. Create a simple signature by pressing the “+” button
  5. Quit Mail App.

  6. Open “Safari” and navigate to this URL:
    file:///Users/<USER NAME>/Library/Mail/V2/MailData/Signature

    NOTE:  Replace “USER NAME” with your user

  7. Your “Finder” should have opened automatically.  Put it into “List” view and sort by “Date Modified”.  You should see a file that looks like a long, random set of letters and numbers that ends with “.mailsignature”.  Right click that file and select “Open With” and use your TextEdit program.
  8. Copy the HTML code from your signature to this file. Replace everything except the final
    <br class=”Apple-interchange-newline”> as that is a carriage return that you want to keep for cleanliness.
  9. Open Mail back up.  Start a new email.  If you don’t have a signature you should see a drop-down menu with the choice for your new signature.  Select it and Voila!  HTML fancy good ness.