Instructions are in Dutch, I made translation for you:
There are 3 drawings:
Till length 116cm, fabric 55x85cm
Till length 152cm, fabric 70x110cm
Till length 176cm, fabric 85x130cm
The apron may fall over, make it rather too large than too small.
Working method:
Draw back and front part in full size and stick the parts together. You make the apron from one piece.
Strengthen the 4 shoulder pieces with an extra piece of fabric (for the buttons and button holes). You can assemble the apron with a band, a seam or decorative stitch. Or you can make the apron of double fabric.
All sizes don't have seam surcharge. If you seam or make the apron of double fabric, then cut 1 cm extra around.
You can make 1 or 2 bags. In the Pippi movies the apron has 2 fairly large square bags (15 x 15 to 20 x 20 cm) to the side.
Make the rectangle, pull a midline.
Turn points on the indicated places.
Pull the straight lines along a ruler.
Pull the other lines as fluid as possible through the points.
Shoulder front piece with buttonhole middle on dotted line: extension with a half circle between the 2 points.
Shoulder back piece with button middle on dotted line: extension with 1 to 1.5 cm between the 2 points.