Trace your basic dress with darts and no ease at bust and waist, 2 to 4cm ease at hips.

Adjust length, then flare by 10cm from sides blending to zero halfway between waist and hip levels.

Draw the front overlap by adding 3 to 4cm past center front, then using the same measurement from center front inwards draw the halter neckline ending to side seam 2cm below armpit. Make sure you have enough coverage above bust point at shoulder dart (this style is quite high so I suggest at least 12cm).

Draw the second line of front bodice starting at front overlap at neckline, crossing center front 3 to 5cm above bust point and ending 2cm above waistline at side seam.

Cut through back neckline, then continue the line separating bodice and skirt: the line starts at side seam 2cm above waistline and ends in center back approx 3cm below waist.

Widen dart at neckline by 0,5cm on each side to have bodice tighter to chest.

Flare center back skirt by 5 to 8cm, then square down from dart apex to hemline.

Cut through slash line that separates bodice and skirt.

Cut through back bodice dart and discard it, then trace a copy of the piece by smoothening lines.

Draw grainline as a parallel to center back.