Here's how to do it. First, select the T-shirts you want to use. Roughly cut out the logo or picture you want to feature. Leave lots of space around the logo... a couple of inches if possible. You will be trimming it later.
Cut medium weight fusible interfacing to fit the back of the T-Shirt. This will help stablize and reinforce the jersey fabric.
Iron the interface on the back of the T-shirt according to manufacturer's instructions. (I never really follow those instructions. I just turn on my iron and do it. That's why I am wayward.)
Some people choose to have all squares the same size. I am not one of those people.
I am going to use a white on white fabric as lattice work. I will be using a bandana print for the back because Ben loves bandanas almost as much as T-shirts. I might use old ties in the lattice work, too. That will be another post if I do.
Here are my all my blocks together and a pictorial history of my husband's adulthood: