How to explain this without pictures?
Ok, if you pattern draft (I am assuming you do) you would draft the pattern for this on tissue with the appropriate details for inserting the darts into the front fold portion and also the extra fabric needed for that twist. Cut the tissue down center front, invert one side (turn it upside down, both pieces with the right side facing up but one shoulder up, one down) and tape back together at centre seam. When cutting you will cut 2, sew neckline and arm holes, then you'll have to figure out how to sew the bottom part of the bodice to the front skirt and hide the bit where the twist is.
I really hope that made some sense to you. You'd sew side seams last and that would just go as any other dress once you'd gotten that twisted bit attached.