Absolutely a harness will be better than a collar, and I think practicing and getting him more used to woodsy places will be good. A collapsible water bowl that you can fill from your own supply, and plenty of treat to keep his energy up are also important. The more leash training you can do, the better, and of course you know never EVER to let him off leash someplace unfamiliar - that beagle nose will lead him into goodness knows what direction!