How to Make a Onesie Skirt

Measure the width of the onesie; call this measurement A.

Cut a piece of fabric that is three times wider than A wide by 10 inches high. Fold over one long edge by 1/2 inch, then 1/2 inch again and press in place.

Sew a straight seam along the folded edge to secure the hem in place.

Sew a basting stitch along the raw edge of the fabric. To do this, sew the longest straight stitch on your sewing machine or use a hand-sewing needle and a long running stitch. Pull on the threads to gather the fabric until it is only two times wider than A.

Bring the fabric together with the right sides facing and the gathered edge on top. Sew down the side where the two short ends meet to make a seam; use a straight stitch 1/4-inch in from the raw edges. Go back over the cut edges with a zigzag stitch to secure the seam.

Turn the onesie inside out. Use a washable or disappearing fabric marker to draw a straight line across the onesie, going right across the center waist area. Turn the onesie right side out again.

Insert the onesie inside the skirt (still inside out) so that the bottom end of the onesie comes up out of the gathered end of the skirt piece.

Unsnap the onesie and fold it out and over the edges of the skirt. Line up the fold with the line you drew on the inside of the onesie and sandwich the raw edge of the skirt between the folded layers of the onesie. Pin the sandwiched skirt fabric in place inside the onesie.

Sew a straight seam all along the fold of the onesie, approximately 1/2-inch down from the folded edge. This will enclose the skirt in the onesie. Remove the pins and turn the onesie dress right side out for it to be ready to wear.