I purchased a strip of canvass 8 feet wide and 6 yards long. I laid it out on the floor and a friend and I drew a half circle 16ft in diameter. We then folded fabric in half and cut out an egg shaped doorway (half from each side). I folded the circle one last time and cut off the point (to make space for the polls to cross). The image below shows my intended design which I deviated from slightly just to make layout as easy as possible.