- In Japan before people eat they say "itadakimasu" ("I gratefully receive"), and after they finish eating they say "gochisosama (deshita)" ("Thank you for the meal").
-It is polite to wait until everyone is served before you start eating.
-Blowing your nose in public, and especially at the table, is considered bad manners.
-Unlike in China, where you are supposed to leave some food on your plate to show you have gotten enough food, in Japan it is considered good manners to empty your dishes to the last grain of rice.
-In many parts of East Asia, it is not rude to burp while eating, even is considered a compliment. In Japan though it is considered bad manners to burp.
-After finishing eating, it is good manners to move all the dishes that you used back into the same position they were at the start of the meal.
-A second helping of rice or soup may be served on a separate tray by the host. The guests are expected to accept the bowl with both hands, taking care to put it down on their trays once before beginning to eat from it again.
-Rather than being bad manners, as most of the western world is generally taught, slurping soup and noodles is considered evidence of enjoying the meal, particularly for males. Mothers will even occasionally tell their male children to eat more noisily, like a man. Considering that spoons often aren't given for eating soup and Asians serve soup hot it would be hard to eat it quietly even if you wanted to (slurping cools the soup/noodles down).
-It is uncommon for napkins to be given at Japanese meals, you should bring a handkerchief or some tissues with you.
For more see my post on Hashi (Chopsticks).