I used to make these for Seat-O-The pants. Take about a 3 foot section of your prussic rope, and tie the two ends together to make a loop, we used a fisherman's knot to do this. Then you can loop your prussic onto your main rope. I would suggest that you loop your prussic three times instead of two, when looped twice it takes longer for the prussic to stop you if you fall. Good luck!