Looking for the perfect way to show off treasures from your travels? Copy and enlarge a map of the area you visited. Cut it to fit inside a shadow box, and use spray-mount to affix it to the back of the box. Fill the box with sand and shells you collected. DIY Tip: Make sure sand won't spill from the seams of the shadow box. If necessary, run a thin bead of wood glue along the seams to make it leakproof.