Purchase a skin. Visit various websites that sell credit card skins and select your favorite.
Design your credit card skin in Adobe Photoshop. Use clip art or photos. Print a test sheet on plain paper to see if you like the finished product. Then print the final design on T-shirt transfer paper.
Cut out the picture carefully. Take your time, patience is the key to an awesome finished product.
Peel the front sheet off the transfer paper and glue it to the front of your credit card with a spray-on mounting glue. Use a knitting needle to push the paper into the holes within the numbers and letters.
Place a sheet of ironing paper over your card and iron it on a low setting for 30 seconds. Any longer will warp the card.
Using the flat edge of an exacto knife, trim any remaining paper from the edge of your credit card.
Repeat these steps on your other credit cards. Let your imagination run wild and use a different design for each card.