8. Do not forget to take your shoes of if you are going to enter a home.
It is better you turn you shoes to face to door after taking them off.

9. Wear the slippers that they have given to you.

10. Do not wear the slippers onto the tatami floor.

11. If you are going to use toilette, never forget to take off house slippers and wear toilet slippers.

12. When you see someone in the morning say "Ohayogozaimasu"  afternoon "Konnichiwa" and evening "Kombanwa" before you go to sleep say "Oyasuminasai! 

13. Do not move independently from the hosts.
Wait for them to offer you to do something.

15. Try not to be too loud out in public
At the dinner table, wait for everyone to say ITADAKIMASU (let's eat!), then you can begin your meal.
There is no real custom like "help yourself". Wait until the host offers something.

17. When sharing a dish, put what you take on your own plate before eating it.
If you are a guest your drink will be continuously topped up by the host, if you serve yourself, it's not too bad, but then you must pour someone else a drink.
If you don't want any more to drink, leave your glass fall.

18. Wipe your hand with the moist towelette before eating and fold it nicely to the side of your setting.

20. Never separate chopsticks from one hand
Never separate chopsticks from one hand. (If you separate the chopsticks, it means you'll disturb the "peace.")
When setting down your chopsticks, never stick them into your food (it will represent your tombstone)

22. If for some reason you can't use one of the chopsticks from your pair, get another pair, don't get a single other chopstick.
Never point chopsticks at someone.

23. When someone gives you a gift give profuse thanks, next time you see them say thank you again. This works for apologies also.

25. Gift-wrapping should reflect current seasonal themes or incorporate seasonal colors. Avoid all-white wrapping paper (it represents death)
All gifts should be gift-wrapped or in a decorative box. The gift-wrapping should be well done and that the paper is not damaged or soiled.
When receiving a gift it is customary to hesitate to open the gift until invited to do so.
It is polite to open the paper carefully, not to rip the paper. The best-mannered in Japan wrap the gift back in the paper as it was wrapped after opening it.