My children were invited to a party with a fairy theme. I tried to convince my boy that he should be a pixie or elf, but he wanted a "fairy skirt" too, so I made him green shiny pants that have strips of the "fairy skirt fabric" all around. For my daughter, I just did a skirt. I like to have a separate skirt for fairy costumes so that it works for all seasons and isn't outgrown quickly.
Both sets of wings were super quick just gathered in the middle, rather than trying to make anything with wire on the outside.