Step 1
First, mirror front to have the full shape.
Then draw the side cutout from center front neckline to right armhole approx 5cm above armpit, to right part of neckline 3 to 4cm past high shoulder point.
Then draw the first line for the other cutout starting from left shoulder line 3 to 5cm past high shoulder point, passing through waistline at right dart and ending in right side seam.