Topstitch that whole top line. I had to use a sheet of printer paper to stabilize it, the machine will want to eat it. Fold over the bottom hem and topstitch it as well.
Back view.
Sew up the back seam 1 inch.
The velcro usually comes in 15mm strips, cut that in half, a 1/6 doll doesn't need that much. Then cut a 1 & 5/8 inche long strip.
Sew both peces in.
Wrap the doll legs in tissue paper so you can dress it without destroying the dress.
Take two pieces of thin ribbon, about 3 inches long, with heat fused edges.
Position them and sew them on by hand.
Rinse it without any soap, just to get the marker out. The "disappearing" ink can still discolor fabrics over time. Do it on a dry day, when the fabric can dry quickly.
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