Light duffle will do. Sunblock. Hat. Water. Beach Towles. Fast speed film for the usually bright days. 400 will do when it rains - you know - the usual vacation stuff. If you want to camp at John Prince Park, you may use any kind of tent. I would suggest to be sure it's water proof, and mosquito proof.
At the beach, less is best for lugging gear over piping hot sand. (trust me) A pair of sturdy sandals, and a decent hat that won't blow away. Sun block on your nose, under your eyes. And try not to expose for more than 1 hour. The sun at the beach is murderous. Just the way I like it.