Good shoes. That's all I can say. It's really fun (go every summer for my dad's b-day) just, if you bring the wrong shoes, you can get blisters. Enjoy the pretty sights, tell me the coolest thing you saw! Also, go to west Yellowstone, get one of those super-cool hoodies. Bring an emergency bag, like a GPS, first aid kit, matches, (just don't light the forest on fire lol) an extra phone, etc.
Have fun!!
