I made this cosplay around the same time I made my Guy Cecil cosplay, which was the first time I'd ever sewed my own cosplay!
The dress I made from a pattern that I altered with a little advice from somebody else who sewed. The sleeves I didn't have a pattern for, so they came out pretty good considering. I painted the green parts on with acrylic paint, (I didn't know about the wonders of bias tape at the time either).
The shoes were a pair of regular black, flat boots, which I then painted the green strips on to. The white parts were made by putting two pieces of white craft foam of the correct shape between two pieces of white fabric, which I sewed shut and glued onto the boots. I made the soles in the front white with white duct tape, hah hah.
For the hat, I ended up just taping pieces of craft foam together and covering it with fabric.
The wig was a pain. I ordered a white wig because I couldn't find a green one that would work, then dyed it using a dark green acrylic paint. The bangs I cut, and then the side bangs and braid were done by a friend.
All in all, for one of my first self-made cosplays it isn't too bad. I'd do some things differently now, but that just means I've been learning!