Waterproof bags for clothing and everything else. A few good poly tarps(solid not woven) for rain and such, you can cover you and gear.Sharpening stone,compass,map, an emergency cell phone, and or SAT phone, and GPS with extra batteries for all electronics.And do let someone know entry and exit dates and times and have an extra map with the route marked on it in case you dont return on time.That is the single best advice I can give you.
And most important, you all should go to your house and watch Deliverance! bet ya get some tips from that...LOL