Place a piece of adjustable mask elastic mask elastic between the fabric, with the loop to the inside Using a 1/4 inch foot, stitch inside the edge of the shape of the batting. Leave an opening for turning. Turn right side out between the layers of fabric. Top stitch around the cozy. Place your button according to the size of your cup. If you place buttons on either side of your cozy, the cozy is reversible. The mask elastic will adjust to snug up against your button nicely.
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