Handy bags for clothing
Well, I have never been to Peru, however my travel tips are valid for all kind of overseas and long-distance journeys: Travel light! Don't bring everything but the kitchen sink. Also, try to keep your stuff organised.
Do I always follow the travel light rule? Unfortunately not. But of course I try to do my best :).
Use a light traveling bag, not a heavy suitcase. You can already take a couple of shirts additionally if your luggage is light. Apart from that, a bag is much more convenient if you have to open it somewhere in a train, bus, or on a car seat.
How to organise your belongings in a large bag when you are on a round trip and stay in a new hotel / cabin / motel every night? You won't unpack each night, do you?
Well, I use these handy bags pictured above. They only weigh a few grams, but they are large enough to hold and keep shirts tidy. Carrying all clothes in these small bags has proved to be the best thing since sliced bread. At least for me.
Light plastic bags do the trick as well.