I did not take any pictures of the making, unfortunately. You make it by draping the bags on yourself, as you would do with fabric on your dress form. Beware: once you start making it, you can't take it off anymore. Wear something nice underneath so you can take it all off in public later (see below). You start with one garbage bag wrapped around your waist, and attach the body and sleeves. Then you bind off 6 big and 6 small garbage bags with air in them, and tape them to the body. The black part is to disguise the tape that holds the skirt part. It would have looked better in blue, but we were out of blue bags. I used 17 garbage bags in total.
Once you're out in the town they deflate a bit because of people bumping against them, but the effect stays. Dancing proved to be a bit difficult, as you get really hot wrapped in plastic. But then, having people ripping the bags off you is also quite fun :)