I am going to be attempting to sew a vinyl jacket for a costume, but I’m really worried about how to sew the sleeves to the shoulders! Any tips? The cut of the pattern means I have to sew up the sides of the jacket first, then sew the arm on (So no sewing the shoulder on first, then sewing the sides of the jacket and the sleeves in one go). The pattern is intended for vinyl, and I have to do some easing to get the shoulder to fit the jacket.
The big thing with vinyl is that holes stay, so you can’t pin it. Instead use tape, magnets, binderclips or other clips to hold it in place. Your ease should be in the seam allowance so it shouldn’t cause any visible puncture holes or structural issues. Just make sure everything looks good before you sew it, vinyl isn’t something you can seam rip.