I would seriously consider calling around to a few dry cleaning shops and see if they can squeeze you in (there's a joke in there somewhere about seldom worn suits). Mamma taught me for wool to set the iron on medium or lower. If the wrinkles are not to bad, you might be able to just hang it and steam it - fill your iron with water, crank it to high and use the steam button without touching the hot iron to the fabric. If your tux is silk, you're on your own cause I don't know.