With right sides together sew the fused/interfaced flaps together along the base and the sides, clip the corners and turn out to the right side. Topstitch around the 2 short and long folded edge then sew a stay stitch across the cut edges (top) of the flap to hold in place and press.
Take the front skirt (1). Using the markings on pattern and the raw edges of the pocket flap, position and pin the flaps into place on the right side of the skirt. Sew the flaps into place, backstitching at start and finish of the seams.
Fold the flaps into place and press, then sew a top stitch across the top of the flap to hold it in place, backstitching at start and finish.
With right sides together, sew the front skirt (1) to the front bodice (2). Neaten seam with an overlocker/serger and press up. Sew a top stitch along the seam on the bodice side to secure in place. Repeat this step for the back skirt (3) and back bodice (4).
With right sides facing sew the front and back shoulder seams together. Neaten with an overlocker/serger and press towards the back.
With right sides facing, sew the two short ends of the neckband together. With wrong sides together, fold the neckband in half lengthways and press. Sew a stay stitch along both raw edges of the neckband to hold it in place.
Pin the neckband to the neck. Once in place, stitch the neckband to the body, stretching the band as you sew. Neaten with an overlocker/serger and press the seams down (towards the body of garment). Sew a topstitch around the neckband on the side of the body.
With right sides together, sew the side seams of the front dress and back dress together. Neaten seam with an overlocker/serger and press towards the back of dress.
With right sides together sew the sleeve seams together. Neaten seam with an overlocker/serger and press towards the back of sleeve.
With right sides together sew the sleeves into the armholes matching the sleeve notches to the notches on the armhole. Neaten with an overlocker/serger and press towards the sleeve.
Neaten the sleeve hem with an overlocker/serger and turn at the notch to the inside and stitch around the hem with a twin needle topstitch.
Neaten the hem of the body with an overlocker/serger. Turn the hem up to the inside at the notch and press. Stitch the hem with a twin needle topstitch.
Press your new dress.