- 1). Turn the youth sized shirt inside out and fold in half lengthwise.
- 2). Fold the onesie being used for a guide in half lengthwise as well.
- 3). Place the onesie on top of the shirt, matching up the folds and neck holes.
- 4). Trace around the onesie onto the shirt, leaving a one inch allowance.
- 5). Cut along the traced line. After cutting you should have two pieces, a front and back.
- 6). Sew the seams together. Keep the right sides of the shirt against each other and sew along the sleeves and sides leaving the bottom open.
- 7). Hem the bottom edge. Cut a small diagonal slit along each side of the crotch where the onesie will fasten together. Fold the edge in and stitch along the leg opening. Repeat on the other side.
- 8). Complete the closure. Cut a piece of Velcro to fit along the closure. Stitch the Velcro into place on the onesie. On the front side the Velcro attaches to the outside. On the back the Velcro attaches to the inside.
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