. I cut thin plywood a inch wider and higher than the blocks that were sewn together to make a row,I added a small side piece to each end of the plywood so it could be attached to the wall, it was about four inches. Then I covered it with batting.Then added enough material to each end and top and bottom of the block strip to cover the bat covered board and stapled it to the board, wrapping the material to the back I then cut a piece of material to cover the staples in the back I attached it to the wall with small L brackets. Your squares are very nice and it would be great to see each one and not have them ruffled. You can add as material between the blocks that you need to fit your windows.