Find a net that can catch shrimp and has a long handle. Go almost all the way to the end of the jetti. Look between the boulders where the water is (at night) and you should have no problems seeing the beady red eyes of the peps. Take you're net, put it as far down under the peps as you can and bring the net up along the rock. Even if you don't see anything but seaweed on the rock, chances are you will net some peps you couldn't see. You are also going to catch blennies, Sgt. Major damsels, anglers, and maybe even a file fish. Just make sure you have a current Texas saltwater fishing license.
If you have time, make sure you hit St. Jo's Island. Beautiful beaches including sandollars and awsome shells. Nice blue crabs out there so watch your feet. There are no bathrooms on the island, no stores either. Nothing but a small jetty and a small boat dock for the ferry. You can only walk on the island so keep that in mind if you go. No roads, no cars, etc. Nice place to fish too.
If you want to know anything else, just let me know. Have a great time.
Chad