Guests come dressed in anything but clothes. A garbage or leaf bag can be made into a dress, grass skirts and coconut bras are welcome as are outfits fashioned out of caution tape or a feather boa.  If you dare, a pool toy can even be worn as a skirt. Guys can wear an empty 24 case with duct tape for suspenders, a tool belt or the beloved bedsheet toga. With the exception of the necessary undergarments, basically people wear any objects or materials found around the house and have a great laugh seeing what everyone came up with.  It's an awesome way to get people thinking creatively and also costs very little for attire. Groups getting ready together pre-party will have a blast helping to 'dress' eachother up in bubble wrap, tablecloths, strings of flowers, or maybe even a little body paint...so of course people are in an up-beat mood when they arrive!  One way to get people really involved is to award 1st, 2nd and 3rd prizes to the most original get-ups. Another fun aspect of this theme is that if anyone shows up dressed in normal clothes, the other party guests get to fashion an outfit for them, using materials found around the party host's house. To make this easier, the host should gather suitable materials before the party begins and put them in a designated spot if this should happen.