User blog comment:BLACK OUT/Wordbubbles./@comment-26531060-20120923015507/@comment-26531060-20120923041921

Tell them how to. It's easy, just create a page with the title is "Template:[insert username]'s Signature" then put anything that user want; basically, edit it like a Wikia page.

Having a signature is the same

What do you mean by "guestbooks"?