Always pack a small towel, as it is useful for drying off and you never know when you may need one. Buy a small backpack around 35-40 liters to force yourself to pack lightly. It is okay to wear the same t-shirt for a few days and only pack half the clothes you think you will need. Be sure to pack extra socks as some will get lost or worn out. Take an extra bank and credit card as a backup in case one gets lost or stolen while traveling. Use bank cards without foreign transaction or ATM fees to avoid unnecessary charges while traveling abroad.