at the back, I cut an arch for the tree. small size 12 x9 large one 15 x 11. I cut the center out, so I did not have to climb around it, but through it instead. I cannot get all around the tree, but i can shoot all around the tree, The heel of my boot hooks on the edge of the side. The first year, I did not cut the center out, and it was hard to get on, I took it down, took my tree saw out , and modified !!. then what I realized i was doing was just making to foot prints for my feet. The Muddy sticks are square ,tubes, so it made it easy to screw to. . I used plywood, , strong, not very heavy, and when I get it where I want, I may make it out of hardwood, ,,, or not. hope this helps, pretty sophmoric in design. The one on the left has the 3 sticks tied together