After a minute to 3 the blood will quit coming out.
The head may stay attached
I put the curve part on the back of the neck and the blade on the front.
Screw the kitty litter jug on something with large washers. The spout needs to be cut out too, so the comb fits through easily.
You'll have to pull the head through the jug sprout. I hold the comb or wattles with my Left hand to keep the neck out of the jug. I cut the neck below the head, but...