Start from bodice.
On back and front draw the shoulder strap by moving the armhole 2-3cm inward, then making the strap 4-5cm wide.
On back, square across the center at armhole height. Then erase the dart and discard it half from center and half from side.
On front, reduce the waist dart and discard half of it from side (to make the side as slanted as the back one), then draw the front neckline. Then widen the bust dart by 1cm at the neckline.