Sew a quarter inch away from that line on each side.
After sewing, cut on that line you drew, then press towards the darker color.
Make four of these and set them aside.
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Next, take the next size of squares and repeat the same thing.
You should end up with eight pieces.
Lastly, take the rectangles and just sew them in pairs side by side.
Repeat to the remaining pieces, then press toward the strips.
Next, sew the smaller half-square triangles to the small dark squares.
Make four pairs of these.
Lastly, sew the remaining small half-square triangles into the small white squares.
Now, take a strip block and sew it with one pinwheel block.
Pair this up with one of the larger half-square triangle pairs, then sew.
Make four pieces like this.