Here's how to do Cracked Glass Technique: Stamp your image on card stock and sponge, distress or punch corners as you like.
Cover entire area with VersaMark ink (tapping the pad onto the paper is the easiest way to do this), then cover with Glassy Glass Enamel. Heat and repeat this step two more times. Let it cool a minute and then bend layer so it cracks. It's very cool.
Then you finish the card as you like!