Mark a opening on the wrong side of the sleeve, about 7,5cm (3 inches) from the back side seam. Reinforce the stitching line of the opening.
Use a short stitch at the point and reverse stitch to strengthen the point. Cut open up to the point.
Cut a binding about 3,5cm (1 3/8in) wide and twice the length of the opening. Press under 5mm to the wrong side of the binding.
Spread the the slash open and pin the binding right sides together. Align reinforced stitching line to the marked seamline. Tack and machine stitch with sleeve side up. Press seam flat.
Fold the binding over to the wrong side to encase the raw edges and tack.
Sew with machine, or slip stitch by hand. Press.
Iron interfacing on the cuff. Fold in half with right sides together and stitch the edges together.
Trim the seam allowance
Pin the cuff to the sleeve with right sides together. Align the placket next to the cuff seam.
Tack the cuff in place and machine stitch. Pull the cuff down and press the seam allowance, while folding the cuff seam allowance in. Bring the folded edge to the stitching line on the wrong side of the sleeve. Pin and tack in place. Machine stitch or slip stitch on the wrong side of folded edge. Remove the tacking and press.