Well, for starters, here's a few tips:
Put a clearly visible "title" at (or very near) the top of your site. This title is the anchor text which lists will use when they link to you.
The "Enter" link should be below the recip links on your warning page.
Write a warning statement of some kind on your warning page, or at least include the words "Restricted to Adults" on the page. Remember, this is a warning page, you need to give a positive indication that your site has mature, adult, pornographic content, not appropriate for under age audiences. While you're at it, check this out:
http://www.rtalabel.org/index.php?content=howto
Also, you can have ads and outgoing links on your warning page. Just try to keep the explicit content off of the warning page.
Let us know when you've added these elements.
