We pack a surplus of shirts, pants, and shoes that we think we might use but never actually do. We include duplicates, because you can't ever have enough white T-shirts, right? We pack chunky sweaters that only bulk up our carry-ons. As a result, we're left paying a lofty fee for overweight luggage and giving ourselves a headache that could easily be avoided.

Look, we know we're not going to change our packing technique overnight. We're human, after all. So if we're going to continue to overpack for the foreseeable future, we might as well be smart about how much space our stuff is taking up.