The wash is the easiest part. It’s just a matter of laying down the lightest tone of each hue. It gives a little definition and a hint of what the color scheme will be. The biggest challenge here will be the hair and grass. If I were a less meticulous painter, I’d simply include just enough detail to suggest hair and grass; but I won’t be able to help myself when I see each blade and tress begging for its place on the paper.
The dress (an original, by the way) is the part I will most enjoy rendering: silk chiffon—one of my least preferred fabrics to sew (although it's way better than polyester), but, by far, my favorite to paint. The facings and narrow french seams actually become part of the design and the challenge.