I have made a dozen or more tee shirt quilts. First i cute the tee shirts apart at the sleeve seams, then the shoulders and then the sides. I use a fusible stabilizer on the inside of each tee shirt. I like to lay the tee shirt face down on an applique sheet because sometimes, the design is a kind of plastic stuff that will melt. The applique sheet helps prevent that. After the interfacing is ironed on, let it cool a bit and lift it off the applique sheet and go on to the next one. After they are all fused, then and only then, cut the tee shirt into the desired size. It takes approximately 1/2 yard of interfacing per tee shirt. I like to cut the tee shirts with the size of design to they will be different sizes. I fill in with novelty fabrics like football prints around a football tee shirt or basketball or music. I also embroidery their names and high school name and class of ???? on the quilts. Each grandchild gets one when they graduate. I have even added Boy scout ranks badges, as 2 of my sons are Eagle scouts. I try to make them personal for each person. I just use my imagination. Anything goes.