The dress without the sash:
I used three panels of cotton voile. I joined them with a selvedge join leaving me with a large rectangle.
Then, although many had commented that the the ribbon channels shouldn't be straight across the dress, I wanted to try it that way. I took out one horizontal thread to mark where the channels should be sewn and to get them straight and then I sewed c. 1/4 inch wide silk ribbon to make the slots.
Then I tried it on and determined the length needed for the straps.
Then I made the sleeves, same size and shape as the one in the pattern, but instead of a drawstring cuff I wanted a similar cuff as in a painting Antoine-Laurent Lavoisier and His Wife. The underside of the sleeves were sewn from the inside and the upper side from the outside. The upper side seam allowance was then covered with a shoulder piece.
The small rump was quickly hand sewn of striped linen and filled with cotton.