Real Simple has a some great tips on how you can pack easy! Tip #2 REDUCE, REUSE, RECYCLE.
While I try to follow this at home with our garbage and compost I don't think this means start wearing plastic bottles and old pizza boxes. Although I seem to remember Marnie in the HBO Girls wearing something like that in her episode as a hostess for the cool art guy.
"Lighten your load further with multitaskers—which don’t have to be those girl-explorer zip-off cargo pants. T-shirt dresses, leggings, tunics, and maxis take you from sightseeing to dinner. Let yoga pants moonlight as pj’s, or use your cover-up in place of a robe. New York City–based designer Yigal Azrouël favors sarongs, because you can tie them multiple ways as a cover-up or a stylish wrap at night. If possible, wear a garment for the dressiest occasion early in the trip, when it’s less likely to be dirty, says Poole. For instance, one tank can stretch for days: Pair it with a skirt and heels for dinner on Saturday, capris and sandals for shopping on Monday, and shorts and sneakers for a Tuesday hike.