Exactly. Ride as much as you can. This will toughen your butt and give you the chance to experiment with foods and/or drinks on the bike.
Having done multi-day tours I can tell you the third day is the hardest. Just learn you body and stay within yourself. If you try to keep up with someone who is just a little bit faster it will wear you out on a multi day event.
Probably no big climbs up there?