I have pretty calussed hands and I just grab them by the lip like a bass. My girlfriend uses a glove and does the same. If it is a big fish, I will not use my thumb, butt, my fingers. This is hazardous because the bigger fish will tear up the top of your hand sometimes. Many people run there hand up the back of the fish (staring stright down at the fish), spreading the hand and placing fingers behind the spines with one or two left on the top to steady the head of the fish.