1. Lift your plateIt's okay to lift small plates and bowls when eating. It's also ok to sip Japanese soups directly from the bowl.
2. YellingStaff at restaurants tend to yell. The louder the better. For example, when you enter a restaurant they'll likely yell irasshaimase!!.
It's okay to yell back at the waiters. When you want something – yell sumimasen!! You'll find this incredibly convenient. Far easier than trying to get eye contact.
3. Eat sushi with your handsHaving trouble with your chopsticks? It's perfectly acceptable to eat temaki, maki and nigiri sushi with your hands (although it looks a little masculine and most people do use chopsticks).
4. Drinking at the beachYour allowed to drink in public in Japan. This one isn't too surprising since most countries allow this (notable exceptions being the United States and Canada). In Japan, it's easy to drink in public — Japan has beer vending machines.
Japan has strict drinking and driving laws. Japanese people don't drive much — take the train if you think you'll be drinking.
5. SlurpingIt's perfectly acceptable to loudly slurp your Japanese noodles such as ramen, soba and udon. The louder the better — nobody will be offended.