Minimize: Keep It All In One Bag
As a photographer or general creative, it's best to pack all working gear essentials into a smaller backpack as a carry-on. This means your: laptop, camera bodies, lenses, SD cards, camera batteries, film rolls, hard drives, chargers, camera accessories, etc. Stuffing the smaller accessories into a sizable pouch will help better compartmentalize your items in a more secure manner; you don't want your SD cards floating around!
Keep the absolute musts (phone, wallet, and passport) at the top pouch of your bag for a quick and easy access. You'll most likely be pulling these babies out quite often during your travels, so it's best to keep them in an unforgettable spot. Jacket pockets work well, too.
Pro tip: put your laptop in the easiest place possible — you'll have to grab this at least once in order to go through an airport security.