Gather the supplies

Fold one of the longer edges of the dress piece by 3/8- inch and press

Fold again by 1 and ½- inch and press once more

Sew down the fold along the edge

Sew a straight line ½- inch above the earlier stitch to form the casing for the elastic

Take the required length of the elastic and insert it through the lower casing, using a safety pin

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