Check customs regulations if you plan to bring back anything exotic. However, some airports do not allow this hand check. You may also place your film in a lead-foil bag. Also, you can have your camera registered at a domestic airport to obtain proof of ownership. Include a small empty bag inside your luggage to use for short trips within your country or to bring back extra belongings.
Small backpacks are a great carry-on.
A passport case that goes around your neck and under your clothing, a money belt, or a waist pack are very handy. U.S. passports are valuable commodities overseas, so keep them handy, but safe. Make a copy of your passport, in case you lost it, as it is much easier to get another one. For the return trip, write your family's name and address on the piece of paper, and place it inside your luggage.