Follow JagMagMan's ideas. With a couple suggestions. 1.) instead of 4x4, I make mine 4 foot by 3 foot 6 inches. Why? The same board of heavy plywood you use for your 3.6 x 4 floor can be utilized to make the 4x4.6 ceiling! (Falling tree branches are not a problem, use tar to seal it). This provides a 3 inch overhang all around the hut. 2.) its easier to make your window openings all the way accross then string a set of camo curtains on a coat hanger (4 pcs per window). Attach the coathanger wire to u nails or screw eyes at the end of each window opening. The windows should be 12 inches tall if you use the flip up style scope covers. I start my windows 36" from the carpeted floor. I also carpet the walls.