I recently made 3 memorial quilts. One each for 2 sister's whose Dad died very suddenly and unexpectedly last Jan, and one for their Mom (that was a surprise for her). They sent me about 30 of his shirts - all sort of tropical themed, and none 100% cotton. I was just stumped about how to proceed, and scared that the final quilts would not be what they were hoping for. I wound up cutting apart each shirt (after washing and ironing) and then cutting each one into as many 5.5 inch blocks as I could. After that I just designed 3 different quilts out of the blocks. The one for the Mom was my favorite. I did a large heart design out of one of the lighter colored shirts, and then surrounded it inside and outside with darker blocks. I put pictures of the girls and the Mom with their Dad/Husband on the back along with the labels. I backed them with just black fleece, and thankfully they were all absolutely thrilled with the quilts.
Good luck with yours. Someone on this board gave me words of encouragement when I was sort of paralyzed before starting them. She told me that no matter the design, the family would love them as a constant reminder of their dear Dad/Husband. She was right!!