Baits to use:
Most silvery bait fish like mackerel, small bonita, sardines, etc should work. You can either cast them to likely spots or slow troll them behind the boat. Barracuda often bite the tail off first and then come back for the rest later, so don’t pull the bait away too early if they do that. Some people like to use a single hook through the nose and a treble hook in the tail to prevent getting bitten off too much. Barracuda have very good eyesight so don’t use hooks that are too large. Wire will decrease your bite offs but also decrease your bites. If you want to tempt fate and retie a lot you can uses straight fluorocarbon with a circle hook and just hope the circle catches in the corner of the mouth before it bites through. However, a wire leader is probably the safer way to go.
Lures:
Great Barracuda readily bite a number of different lures, usually if they are fished quickly and erratically. Often caught on trolled plugs, casted and retrieved jerkbaits, and trolled rubber skirts. Whatever you use, make sure it can withstand the fish’s teeth!