I use offset circle hooks, and I like to "nose hook" my live bait. There's a thin but strong ridge on the top of the baitfish's "snout" that I pass the hook under. The reason that I think this works well, is that the circle hook basically screws itself up into the side of the flathead's lip when the line moves to the side of its mouth, as the fish takes the bait and moves away from the slip sinker. Since I'm placing my hook towards the top of the baitfish's head, I figure I've got a better chance of hooking the catfish's upper lip, or the upper part of his inner mouth. With that in mind, I'm careful about which way I put the hook in, right to left, or left to right, since one way will result in the hook's offset placing the hook's tip nearer to the top of the flathead's mouth, while the other way puts the hook's tip closer to the center of the baitfish's head. I find that when I do it this way, I get a lot of hook ups with the hook in the side of the flathead's upper lip.