I thought it would be fun to make some t-shirts for my family to wear on our trip so I took an image and used an iron-on application from Michaels. I read and followed the directions carefully. Unfortunately, my shirts are not holding up to washing. The image is really wrinkled and cracking. AUGH! What am I doing wrong? Is it me or should I only expect to get to wear them a couple of times? Hopefully someone will be able to give me some advice. Thanks for your help.