i have used this tool several times and love it. It took me a couple of times to get it work right but it is so much easier and cleaner than anything else I have used. I usually cut around the anus from the outside the stick the the buttout tool in and twist. Make sure you twist until you cant anymore unlike the directions say a quarter or half a turn. Usually will twist once or twice, that it doesn't slip out. Once twisted just pull and wham'o its done. I don't tie off the membrane but just cut and then grab onto it from the stomach cavity to keep from anything spilling. My butcher told these tools were one of the best things invented for field dressing if used right.