We built one out of cardboard and a metal frame. Made a window to shoot out of it also. Just open the cut-out window and pull your bow back. You have to be in an area that has a lot of cows or the animals are used to seeing cows. If there are a lot of elk seen also, the elk decoy would work just as good. Take your time getting close and not rush. Watch the wind too.
It was light enough that only one person could carry it, but big enough for two people to hide behind.
What worked good also, is a buck and a doe combination. Make it where you can adjust the horn length of the buck, as you can adjust to the behavior of the goat.