Don’t tip in Japan.
Service at restaurants and hotels will likely be exceptional in Japan, but tipping isn’t done; and it could be seen as degrading.
Don’t smile at strangers in Russia.
They’ll see it as an intimate gesture, indicating a genuine affinity toward another person. If you don’t know them, they might consider you insincere.
Don’t use your left hand in India.
The left hand is thought of as unclean in Indian culture, so always use your right hand to greet someone, exchange money, or pick up merchandise.
Don’t eat everything on your plate in China.
That shows your host didn’t provide enough food or a filling meal. Along with leaving a little, it’s fine to burp after eating, as a compliment to the chef.
Don’t talk with your hands in your pockets in Germany.
It’s considered rude. It’s also customary to keep your hands on the table while eating, rather than resting them in your lap.