No bait required. Just put the trap in a location where fish travel with the sides that have the funnels facing the two directions the fish are likely traveling. I usually put the trap in about 3 to 5 feet of water so it blocks the water column from top to bottom and with the openings pointed each way along the shoreline. As the fish travel the shoreline they bump into the trap and end up inside. It's all a matter of taking advantage of their natural tendency to bump up against anything in there way and then attempt to work around the obstacle. Ever seen fish in an aquarium as they follow the glass around for a long time after you first put them in? They just naturally check out the boundaries. They aren't smart enough to realize the hole and funnel just channels them to the interior. Then they aren't smart enough to get out. I catch plenty of crappie and BG but almost never a bass. I'm not sure if bass are too smart or if they simply have a tendency to stay away from obstacles rather than follow the edges of them. If you really want to increase its effectiveness you could add side wings that reach out and funnel the fish toward the trap. It could get a lot more elaborate if necessary but this design works well for me.

Gotta get back to fishin!