You walk out, chase the tide if you will. You will not be welcome if you drive out to where the clam bed's are in Cholla bay. It's very simple really, all you need is a rake, but I've done well enough by hand. When you get almost into Cholla, the first local house's on the right, you will probably see some cars and people out to the right where high tide line is, and some will have followed the path out onto the floor of the bay.. You might have to cut across a few times, but you will come to a fence that go's toward the water, follow it. If you just watch what the locals, or others who seem to know what their doing, ask, or just follow what they are doing, and you should do fine.
Kenny