What you need for your skirt is:
Start with a rectangle that is 2 times your waist measurement plus 1 inch for seam allowance by the length you want the skirt to be plus 3 inches for the elastic casing and hem.
Abby's measurements were:
- Waist 21.5 inches
- Length 10 inches
While your skirt is still right sides together fold the bottom up 1/2 inch and press then fold it another 1/2 inch and press. This will be the finished bottom of your skirt. Stitch close to the folded edge.