As already suggested get out and get some river miles under your belt BEFORE you do a float hunt. Get the oarsmanship down, sort out how you pack and stow your gear. Initially you'll bring all sorts of stuff you think you might need and after a couple of trips you'll pare that list down as experience lets you better analyze your gear. Take good notes and photos on these first trips. Test your gear and be honest with yourself--maybe your dry-bags aren't, or you brought too much rope, or not enough.
Consider bringing along some 5 gal pails and filling them with river gravel--they'll be about 100lbs each, and see how your raft manuevers then. This is to simulate the weight of a moose. (it will change the way you approach this hunt, promise)
Floating is an awesome way to hunt but like everything else it's always best to be prepared.