I think it depends on what its for. A tickling related one can go into the tickling discussion np. I know that some models have in the past posted things similar to patreon there. General discussion is probably your safest bet. If it's writing related, I believe you could post it in any of the story forums. If a mod thinks its misplaced, they'll move it, and posters will suggest a more appropriate channel if they see one.
You also have a footer/signature/whatever its called to take advantage of, if you wanted.
Additionally, if you're posting content, I would post a link to the patreon each time you do commit content to the site.
I don't get on much so if you want to discuss it further feel free to message me. I'm not a mod though.