Let’s draft the pattern of this evening dress.
Start from a basic dress with darts and a basic sleeve.
On both front and back, lower from the shoulder point 5-7cm along the armhole, then take off the same measurement from the front and back sleeve cap (armhole and armcye should match exactly).
On the front, draw the underbust line and draw the overlapped part to the other bust point.
Widen the shoulder dart by 1cm at the neckline to have the bodice more fitted, then draw some slash lines for the dart manipulation/draping at the underbust.
On both front and back, discard the waist darts by taking their volume from the side seam and center back.
On the sleeve, draw the cuff 10cm high and at its half draw the sleeve wider.
Trace the front bodice separately and cut through all shlash lines, eliminating the volume of all darts.
Separate the little pieces evenly to create the drape and mark all the pleats with notches and arrows to have the sewing reference.
Get the sleeve and draw some vertical slash lines.
Cut and separate the pieces adding more volume for the gathering, then mark it on both upper and lower edge.
Here is the full pattern: back, front bodice, front skirt, sleeve, cuff.