To fish with a plastic grub or a plastic worm, rig with a lead head so that the lure will go to the bottom and "swim" back to the boat, imitating a crayfish or a baitfish. First, cast your lure out to a likely spot like a rock or a tree or some place that looks like a good habitat for a fish. Let the bait hit bottom because bass like to watch it come down. They will swim over and inspect the lure on the bottom. You can raise your rod to lift the lure up and down or you can reel in the lure slowly and gently all the way in. On any given day, the fish will prefer one retrieve to another so try both methods when fishing with plastic baits.