Download the pattern, then print and follow the cutting guide. With right sides together, position the back opening placket over the centre back. Stitch adjacent to the centre line, angling the sewing towards the point, then pivot and stitch back up to the neck edge. Snip down the centre line and carefully into the point to form the opening. On the right side, press the seam towards the placket. Apply fusible interfacing to the wrong side of half of the button tab. Fold the tab in half, right sides together, and sew down the sides taking a narrow 5mm seam. Turn the tab to the right side and press.

Make a buttonhole that corresponds with your chosen button in the centre of the tab close to the folded edge. Undo the stitching on the left side of the placket, 1.5cm down from the edge. Make a gap just wide enough for the button tab to slip into position. Place the tab into the gap with the raw edge towards the placket and the end of the buttonhole, just slightly away from the placket seam.

Restitch the gap enclosing the tab and trim off