I always roll my clothers, put them in a 2 gallon zip lock bag (or 1 gallon if shorts & top), zip the bag halfway, then squeeze all the air out and finish zipping the bag. Makes it easier to pack, outfits are already matched, it's easy to count outfits to make sure I have enough clothes, and if they inspect my bags at check in, it's easy for the inspectors to put all my stuff back. Only thing is be careful, because it also makes it easy to overpack, going over the weight limit for some airlines.