This happy summer dress reminds me of Man Men and Mod Cloth, with the full skirt and wide collar. I was inspired by several dresses from the latter:
Think wide collar, natural waist, full skirt, sleeveless but not strappy.
I had a sort of dumpy wrap dress pattern, Simplicity 3877, so I used it with some modifications.
The collar was sort of a trial-and-error, but it ended up working. I took the collar piece and added a curve, see?
I used the collar as usual, with some of it being on the bias, and added pleats above the bust like the darling plaid frock above.