As well as there are table manners in the West, Japan has its own rules for eating.
Once you are in Japan, it is wiser if you avoided doing what you shouldn’t do.
Don’t make noises when you chew food
I acknowledge that most old Japanese don’t follow this rule, but I don’t think it’s considered to be well-mannered to make noise when you chew food in general. Some people are allergic to the sound, so don’t open your mouth while chewing food.
Slurping is totally fine. Don’t apply the Western culture to Japan
As most of you guys know, it’s totally fine to make slurping sound when you eat in Japan. It doesn’t matter if it’s noodles, soup, rice or dish, but the Japanese just make slurping sound whenever they eat or drink something.
Keep in mind that it’s the proper manner in Japan and the Japanese are not being rude. Even if it’s considered to be rude in the West, your rules don’t apply in Japan.
Your lips, teeth or tongue can touch chopsticks
This might disgust you, but it’s totally fine if your lips, tongue or teeth touch your chopsticks if you don’t lick them too much.
In the West, you don’t ever touch utensils (fork) with your lips or tongue, but touching your chopsticks with your lips is the proper manner in Japan. This is why they sometimes use the back of the chopsticks to share food with others.
Don’t ever pass food from chopsticks to chopsticks
Passing food from chopsticks to chopsticks can only be done when you pick up bones of the dead at funeral. Doing so for food that live humans eat is the WORST omen in Japan, so don’t ever do that. Even if it hadn’t been related to funeral, the action alone would look so ugly and rude anyway.
Also, even if you are not familiar with the Japanese funeral culture, I think you can imagine how passing food from a fork to fork would look like. You wouldn’t do that in the West either, would you?
Don’t stick chopsticks on your food
Sticking chopsticks on food (especially rice) is another custom the Japanese do for the dead and never for live humans. As chopsticks sometimes just roll away, it’s easier to stick them on the rice, but you shouldn’t do that.
Don’t stub food with your chopsticks
For those who are used to using a fork, you might feel like stubbing food, but that’s what you must not do. Stubbing food with chopsticks is considered very rude.
Children sometimes do that because they can’t still use chopsticks well, but adults don’t ever do that.
Don’t stand up while eating
I think this is the same in the Western culture, but it’s considered rude to stand up during meal. If it’s urgent and you have to run to the restroom, at least say “excuse me” (“gomennasai” or “sumimasen” in polite Japanese, and “gomen” in colloquial Japanese).
Don’t use your smartphone while eating either.
Don’t swing around your chopsticks over the dishes
Even if you are not sure what to eat next, don’t move around your chopsticks over the dishes. It’s called “mayoi bashi” (meaning “stray chopsticks” or “lost chopsticks”) and considered ill-mannered.
If you are not sure what you want to eat next, put your chopsticks on your chopsticks holder or on a dish and look around without swinging your hand or chopsticks.
Don’t put your elbow on the table
Putting your elbow(s) on the table is a bad manner in Japan. While eating, pull your arms and try not to touch the table with your elbows. If you want to lean against the table, at least touch your front arms and not the elbows.
Don’t hold your chopsticks like drumsticks and hit dishes with them
Holding one of the chopsticks with right hand, the other with left hand and hitting dishes in front of you is considered to be EXTREMELY rude. Even if you don’t know the Japanese culture, you should be able to imagine that such a behavior wouldn’t be polite in any culture.
I don’t think well-mannered Westerners hit dishes with a fort or knife.
Hold chopsticks in the right way
There is a proper way of holding chopsticks. It’s hard to explain just in text, but try to hold one of the chopsticks as if you hold a pen, and hold the other to assist it. The first chopstick needs to be held firmly, but the second chopstick is only held lightly and it’s the chopstick that you move and hold food. The first chopstick should hardly move.
The Japanese are generous to foreigners in general, but they are very strict about how the other Japanese hold chopsticks. If a Japanese sees another Japanese using chopsticks in the wrong way, he might even say “I don’t want to marry her (or him) because the way she holds her chopsticks is so ugly.” (From my experience, men are more strict about this.)
It might be hard to follow Japanese manners, but if you visit Japan, you should at least try avoiding what is considered to be rude.