You can use your scraps and still center your stamped image by simply using a Post-It-Note “handle,” thus enabling you to extend your reach as you punch. Take scrap of card stock and stamp as desired.
Attach a Post-It-Note to one end of scrap. Feed into punch and center. Punch out image. Voila! You have a perfectly centered and punched image using only a scrap of card stock. Don’t throw away those small card stock pieces! Punch them into shapes of your choice.