Packing travel bags and luggage well is a skill. If you want to be good at it, you have to practise, just like anything else.
Photo by Paul Robertson.
When Bekah Defelice at Thrillist asked a bunch of soldiers, airmen, sailors and other US military personnel for packing tips, the most common suggestion was to practise your packing. Over and over. When you're leaving for a trip, pack your bag, then unpack it completely, then repack it again a few times over. You'll get better at packing your bag so you can do it faster -- which is helpful when it's time to head home -- and it forces you to memorise where every item is in your bag. If you need to get to something quickly, you won't have to waste time digging around. While you're practising, lay everything out in a staging zone, like your bed or kitchen counter, then get to it. Pack, unpack, repack.