Learning local customs can be tricky when traveling internationally. Knowing when to tip and whether it's polite to shake hands with strangers is challenging enough, but even trickier is figuring out your destination's bathroom etiquette.

Some European cities have tip jars in bathrooms. In past years, in European tourist cities such as London and Paris, people often had to pay to use public toilets. Today, many coin-operated facilities are free for ethical reasons, but there are exceptions - Amsterdam, for example, is still a land of pay toilets - but paying is now usually optional. Tip: Waiters sometimes put large bills into the tip jar to confuse tourists. Usually a tip of $0.50 to $1 is enough.

If you've been to a public restroom in Singapore, Thailand, India or China, you've probably seen squat toilets. These types of toilets are common in many Asian countries. When using a squat toilet, make sure your pants pockets are empty or secure. Lower your body over the bowl. If there is a pedal that you can flush with water or a bucket that flushes away waste, be sure to use it. Also pay attention to splashing water.

One of the most embarrassing things to do in a public restroom is causing a blockage. The easiest way is to throw toilet paper in the trash can instead of the toilet, or use a bidet instead. In rural areas of Turkey, Greece, China, Montenegro, Egypt and throughout South America, toilet paper should generally not be flushed.