We usually bring a change of clothes as well, so that we can shower, change and we usually go to dinner from there - or to DTD. You can rent towels there, if you dont want to lug them around, they are maybe $3-5? If you are staying all day, I think you can even bring a cooler if you want, there is a great beach with shade cabanas, but get there EARLY as they fill up. We also use the lockers, but just for wallet/keys and camera. You actually dont really need a camera as there are lots of photopass photographers at the water parks.