Hmm we had our guests book before we sent out the invites. That was just more or less a formality, although we did have a few book after we sent them as well. We didn't do anything special. Our invites were a booklet type, with diff pages being diff entries. One entry was the story of how we met (which Amy) helped with one page was our itinerary, one page was the description of cabo and the event and one was the RSVP. Most ppl responded quite well to that.