Glue and screw the two-inch sides of the 30-inch and 32-inch 2-by-4 timbers to the edge of the plywood sheet to form a box.
Cut a 24-inch by 24-inch square hole in the center of the plywood sheet using the jigsaw.
Place the Plexiglas over the hole. Place the 26-inch2-by-4s at each end of the Plexiglas, and screw through the outewidth of the 2-by-4 into the ends of the 26-inch, 2-by-4 to hold in place. The box should now have a three-inch compartment at either side of the Plexiglas window. Use these compartments to hold your drawing tools. Clear silicone caulk can also be applied to hold the Plexiglas more securely.
Stand the box on top of four blocks or anything tall enough to allow two lamps to sit below, and shine their light up through the Plexiglas.
Sprinkle a layer of sand over the Plexiglas, obscuring the light from the lamps. Using your finger, draw a line in the sand, and the light will shine through.