As suggested try using a float. Set up a sliding rig so you can vary the depth easily with the tide. For bait, my order of preference is live shrimp, dead shrimp, live sandeel, dead sandeel, mackerel strips, rag worm. Tackle shops are usually full of the sliding floats you need with the right size bullet leads to go with them. use size 6 - 2 hooks, depending in bait size.
Example rig : http://www.ni-wild.co.uk/forum/fishing/float-fishing/