This project requires one 4'x8' sheet of plywood. I chose a .451" sheet at my large home improvement store. I had them cut it in store. They do 2 cuts free usually and its something like 50 cents for additional cuts at most of the big guys. Cutting it enabled me to carry the wood home without breaking my back and so it fit in the car. The first cuts are usually the most awkward ones and having the employees do it with the big machines its easier and saves time. The first cut was to slice it down the middle into 8' lengths 24" wide. Now the blades will eat some wood so ask them to make one side be 24" and the other side to be whats left over. Then have them cut both halves at 24" deep. you will be left with an 72' x24", 24x24, a 24"x(a little less than 24"), and 72"x(a little less than 24". One big sheet and one 24x24 inch will make the outer box and the smaller big sheet and 24x24 will make the inside box; this why its okay if one half has smaller parts. If you want you can have the employee cut 2 more pieces 24" wide (so about 24x24) on each large sheet to save you the trouble of doing it yourself at home.