You will need to reprint your Fun Pass so that the VIP shows up on it.
Your luggage tags will have VIP on them as well.
This gives you Priority Embarkation. We have never cruised out of Port Canaveral as a VIP yet (we will be doing that on May 16th...right after y'all get back)...but there will be Carnival Reps there to direct you.
Some ships also give Priority Debarkation when you get back...but that is not as consistant from ship to ship as it should be.