Guard against sticky fingers. Whether you're planning to check your luggage at the counter or have a carry-on, you need to keep your eyes on your luggage at all times. Even if you plan on stopping at a restaurant of have to use the restroom, luggage should be at your side.
Skip the expensive designer luggage. It's tempting to buy the best designer bags for travel, thinking that they must be better quality. But when you pack all of your travel things in expensive luggage, thieves figure that all the stuff inside must be expensive, too. Use cheap, inexpensive-looking luggage, and they won't even give your bags a second glance.
Place your valuables into your carry-on. Before you approach the security checkpoint where you have to go through the metal detector, take off all of your jewelry and watches and put them into a pocket of your carry-on. Don't put them into a tray at the walk-through point, leaving them vulnerable to theft.
Hold up the line at the metal detector. Forget that there are 20 anxious people behind you. Make sure that the person who preceded you has collected his belongings and is on his way before you place your luggage or laptop on the conveyor belt. Then you can go through the metal detector at about the same time as your belongings.
Land, disembark and run. Well, maybe not run, but get to the baggage carousel as quickly as possible. There aren't any attendants standing by the carousel, and even if there were, they have no way of knowing if a traveler belongs to the bag she removes. It's best to beat the luggage to the carousel.
