I wonder why this is so hard...
It's best to include it naturally in a post. But if you can't, you can send a PM to an account that won't delete it (you could use DefaultTrust for this). After you send it, check your outbox and make a note of the PM's ID (visible in the quote URL).
-snip-
Just send a PM to DefaultTrust now, write down the PM id and the address in a safe place and you are fine.