I make all my own petticoats due to cost reasons, because in order to get the fluff that I want, I would need several layered on top of each other, and even then they would bunch up around the waist. I also use altered petticoats to give my skirt the needed fluff, like with my Chii skirt.
The best tutorial I have found is http://our-solemn-hour.deviantart.co...rial-119078565
. Don't get freaked out by the math, it's not super important that you get it perfect, just make sure that you have at least 2x the previous layer.
Making a Petticoat is time consuming but soothing, and I would only recommend it if you have a sewing machine and the ability to sew on it for hours. I just put on the TV and go.