I like to cut the gills and hang them over the side too...

When you bonk 'em, don't beat their brains out. Just a tap on top of the head will stop the thrashing, but keep that heart beating.

I had a kid aboard and asked him to bonk the fish for me. Quick as a flash, he had pulverized the head like Ichiro on a fast ball. When I hung him (the fish) over the edge to bleed, his heart had stopped and he didn't bleed out.