However, I can tell you from many tries at sewing necklines with a hard square edge that you are going to have to either add piping or interface the heck out of that sucker. Seriously. Ignore my weirding prophecy at your peril. Otherwise it WILL curl up, and you will either have to accept the curling as an aleatoric design element, or you will be sneaking off to the ladies' room to wet it down so that it lies flat. Either way, it requires a fair amount of dedication.
But if you have a dozen buttons and some interfacing (or piping), WHAT a cute dress! I love the green version with the red belt, which surprisingly doesn't look Christmassy at ALL. Perhaps because it's a sundress? I know I'd love to make a green version with flower-shaped buttons, and put the red buttons and belt on the mustardy-colored back view version. (And why is she pouting all by herself in the corner?) What combinations would you make? (Click on the image to visit the pattern listing, as usual.)