Lay it down pointed at your target. Tee the ball up on the outside of it (the box is between you and the ball), and up at the front. This makes you carry your arms and helped me improve my pivot somewhat. It keeps you on plane and helps deliver that sweet spot.
I also use it with irons when I am struggling, only I put the ball at the back of the box and between me and the box. It helps me not crash through the wall.