Mark and cut out simple card templates. One the width of the gap and one half width of a pleat.
Now we want to position the pleats evenly all the way around the skirt. The centre front line and centre back of the skirt I am making will be inside of a pleat.
The back seam of the skirt is still open. There is very little measuring using this method once first 2 pleats are sewn in.
Mark the seam allowance width clearly. Then measure half the width of a pleat each side , so for this skirt half a pleat is 8cm.
From this line measure and mark the width of one gap, 7.6cm.
Fold the fabric over, measure the width of half a pleat as the fabric is double and sew a straight line 5 cm deep.
Now repeat at the other end of the skirt waist.