1. Place glass on top of foam core board and trace around the edges. Add two inches around traced area and cut the foam core along the outer lines. 2. Cut the corners from the foam core and lightly score along the traced lines from the glass piece. Bend edges along score lines to create a box that is about two inches deep. 3. Place clock mechanism in the center; trace around it, and then cut three sides and score the fourth to create a window. Also cut a small hole for hanging.
4. Tape box at corners and put into back of frame. If it isn't snug, re-cut as necessary, and then tape the corners together.5. Place glass on top of mat board and trace around the edges. Add 1-1/2 inches around the traced area and cut the board along the outer lines. 6. Cut out the corners and score along the inner lines as above. Cut a hole in the center for the clock mechanism. Spray the mat board with adhesive and cover with desired paper. Trim excess, and then tape the board into a box shape as above. 7. Assemble the clock mechanism on the mat board box and tape it in place. 8. Set the glass in place; top it with the mat board box, and then the foam core one. Secure the latter to the frame with tape.