1. Let casting dry completely. Then varnish the casting to seal it before painting (so wet paint won't make design disappear). Let dry. Optional: Apply a 2nd coat of varnish for more permanence. Variation: Varnish only the raised design and leave the background unvarnished.
2. Apply paints one at a time. Let dry between coats.
3. Optional: Apply another coat of varnish to protect painted casting.
4. Cut papers to fit your card and then to fit one over the other leaving a nice border. Glue 3 pieces together and let dry. Then glue them to the card.
5. Glue casting to center of top paper on card.