If you are fishing for bluegill, use the smallest hook you can find. If you can see where they are "bedding", they will bite at anything that touches their beds in defense. We catch a blue million just about everytime we go.
Catfish, you will need a larger hook, preferably a circle hook. After dusk is the best time, especially in a pond, but more because the bait thieves are sleeping. We catch more on live bait than dead bait. We went a few years ago and caught over 300# of channel cats using baby bluegill for bait.