Create a PVC pipe frame for the liverpool. Mine is 5' long and 28" wide. The tarp I used was a 6' X 8' blue heavy duty tarp.
Lay PVC frame on top of tarp at far end of tarp. Secure end of tarp to side of PVC frame.
Roll frame from far side of tarp to other side of tarp so that frame is completely covered by the tarp.
Secure tarp to frame with zip ties as you cover frame with tarp.
The finished liverpool will hold water.
Finished jump. I've added flowers on either side as a filler because my liverpool is not very wide. I've found a more narrow liverpool seems to be easier to introduce to green or young horses.