You can book a tour or if your car has 4-wheel drive and can drive in the sand you can drive on to the beach yourself to try and catch the wild horses! If you decide to go the self-driving route I recommend going earlier in the morning or closer to sunset to try and catch the horses running around!
Near Happy Belly is the Water Boy rentals! When down in Hattaras for the week Nicole and her Family have rented bikes from the waterboy and typically Bike around Hattaras area. The Water Boy also has kayak rentals for a few hours if you are looking to Kayak around the area! They will drive the kayaks to the water entrance and let you know which way to go!