Doris Petticoats have been a longtime favorite of mine, this U.K. brand makes a wide variety of colors, prints, and best of all, lengths to suit whatever garment you're wearing. They're made of layers of soft nylon which makes them incredibly comfortable, and the ruffles at the hem give you extra fullness and flounce. I just received my favorite length (21") in pink, which I layered with gray in one of the photos, and it's a fantastic combo. They're easily adjustable too, and have a pretty satin ribbon for an added touch.
Right now they're having a giveaway on facebook, you can enter here!
Petticoat c/o Doris Petticoats