Hi! This is Jon on behalf of Expert Village. In this video clip, we will be laying out the bottom. Our bottom piece is going to be coming out of our sheet of plywood right next to our top piece. We are going to do the same thing in making that cut across the entire sheet of plywood. Our overall bottom measurement is 70 1/2 by 10 inches deep. Howeer, it is going to be going on the inside between these two sides. The sides are going to be 3/4 of an inch thick so we are going to subtract and 1 1/2 from that width. Now the depth of it is 10 inches, but we are going to put trim along the bottom. That trim is going to be 3/4's of an inch. So on that depth, we need to subtract 3/4's of an inch. So after you do all the calculations, our total will be 69 inches long by 9 1/4 deep. Our top piece is going to be coming out of one side and we are going to come back and make a second cut for our bottom piece. Again, we are going to make these cuts go all the way along and we are going to come back and cross cut off to the desired length.