Cut two 1-foot diameter disks out of a sheet of cardboard for the cage, one disk for the top and one disk for the bottom. A template can be created by drawing a dot in the center of a sheet of cardboard and then drawing 5 lines through that center dot with a 12 inch ruler forming 16 equal slices as shown in the picture on the left. Draw a line across the ends end of those lines to make a hexadecagon is a sixteen-sided polygon, close enough to a circle. This can be used as a template for the second circle. The disks look like pizza trays.