I was just looking for Tucker block instructions when I came across your posting. One gal in my guild who showed us how to make it had us make four-patch blocks with charm squares. Then we made cuts through this block about an inch and a half on either side of the middle seams, both vertically and horizontally, which then gives you nine patches. You turn the four rectangles 180 degrees (the four corner and middle patches are squares and stay put), and then sew it all back together for the Tucker block. I'm not exactly sure I stated this correctly, so try it on four old charms that you don't care about first.