Measure the area between the clothes racks. There must be at least 8 1/2 inches between the racks to create a shoe rack that will fit between the two clothing racks. Take that measurement and divide it by eight and one half. This is the number of squares you will be able to place on each level of the shoe rack. Each pair of shoes will require a space 6 inches high by 8 inches wide by 12 inches deep.
Rip the plywood into pieces 6 inches and 8 inches by 12 inches with a circular saw. You will need two 6-inch pieces and two 8 inches pieces to construct each box.
Construct several 6-inch by 8-inch boxes and secure them with screws. Do not attach them together.
Place as many boxes as possible between the two clothing racks. Attach two 6-inch plywood sections directly above those on the block. Secure a second finished block on top of these two 6-inch boards.
Repeat Step 4 until you have assembled a complete shoe rack. If you like the natural look, leave it as is, otherwise paint it to match your interior decorations.