Fold the outside covers of the book in half, as you did with the first page. Place the book on your masonite square, and then mark it to size, the open size of the book should be the same as that of the masonite board. Trim off the excess masonite board using your jigsaw if need be.
Place the book on the masonite square, and then trace the circle onto the board. Then draw another circle approximately 5mm in. The inner circle is where we will be placing our mirror, and the larger circle is to allow some room for the wiring on our LEDs.