You can either get to the beach through the National Park it self with an all-wheel-drive vehicle a 4-door sedan won't make it, since you wont be going through a paved road; it is almost as going through the Australian Outback.
You can also get to the beach with a boat. Once you get to the entrance of the park, there's a restaurant called "La Cueva" Spanish for "The Cave" that also has a few boats that will take you to the beach for a reasonable price. The ride takes about 10-15 minutes.
