1. Place two pieces of 4″x7″ flannel on two pieces of 7″x7″ flannel, centering smaller pieces on top. Repeat with remaining flannel squares.
2. Join small and large pieces together by stitching down center of all four layers of fabric as pictured. Stack the two sets of flannel on top of each other, with the small pieces on the top and bottom.
3. Next, make the casing for the Swiffer duster handle. Fold the small pieces of fabric to one side, align the base of the prongs at the edge of the fabric, and center the prongs over the middle seam where the small and large pieces were joined together.