Pack things that easily mix and match. You honestly just need enough "real clothing" for 4 days if you do that. Or two (or three if it fits and you tend to be a more picky person) sets of clothing for every condition with interchangable pieces. Bring more socks and underwear than you think is necessary given the undetermined laundry situation. Travel packs of shampoo, etc are your friend space wise, but economically it may be best to get yourself a family size. I get one of the ones from Suave to last me four months or so at school with daily showers. Roll things instead of folding them. Pack with heavier items on the bottom. Zip lock bags of varying sizes are always a good thing. That's all I can think of. I'm going off of what I typically pack for camp, I live out of a single suitcase there.
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