You sew five 2.5 strips together, then cut them into 10.5" squares. Put one square on top of the other, with the stripes going opposite ways (top square stripes go vertical, bottom square stripes go horizontal) and sew a quarter inch seam all around the perimeter. Then you cut the square in quarters diagonally, like a big X. This will give you 4 blocks, which you then play with on your design wall.
Super easy and fun. I'm making one right now where I alternated light and dark fabrics.
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