Some Serious Questions

While reading the article about the 450 women who posed nude for Spencer Tunick's photography project, I thought, where did these women put their clothes? I don't think they could have just put them on the ground because there would be too many potential mix-ups when it came time to put their clothes back on. Did the women deposit their clothes with someone then? But then they would have to carry a receipt or tag around with them, which would not look good in the photo. I guess they could have lied on top of the tags to conceal them, but what if the tags were metal and cold to the touch?