Answer:
Though Japan is one of the most advanced countries in the world in terms of technology, the Country of the Rising sun is one of the Asian countries that maintains their traditional culture and ways, they can welcome you with warm arms (though sometimes their climate is cold) but they can be warmer to you if you can thank them properly and be polite to them.
First, you must know atleast the basic words of their language (Nihonggo) which is greetings like Ohayogozaimasu (Good morning), Konnichiwa (Can either work as "Hello" or "Good afternoon", depending on the situation), Moshii moshi (Pronounced as "Moshii mosh". It's "Hello" in English but often used in phone calls.), Konbanwa (Good evening), Oyasuminasai (Good night), *Insert desired place or establishment to go to (Must be in Japanese accent)* e no michijun o oshietekudasai (Can you give me the directions to *Insert place that you want to go to*), Itadakimasu (You must say this before eating your meal, it's "Thank you for the food"), Arigatogozaimasu (Thank you), DĹŤitashimashite (You're welcome).
Second, do remember that they take off shoes before entering the house like any other Asian country. So, you should take off your shoes before entering. They often walk barefooted in the house but they have slippers to use that's assigned in different rooms such as the all around slippers that can be used anywhere in the house and the bathroom slippers which is obviously used in the bathroom. Sometimes, some restaurants will ask you to remove your shoes before entering their restaurant.
Trash cans and bins are very few in the streets of Japan, so it's advisable that you should bring a small plastic bag with you if you have small trash such as used tissues or sticks from street food.
Don't just try to tip anyone in Japan (Taxi drivers, waiters, or bartenders), you shouldn't tip them at all. They don't tip in Japan, they might find it insulting if you tip them.
And lastly, you should and must respect the rules on the subway. People take the rules seriously and you should too. That means no talking on cell phones and no food or drinks. Make sure you don’t sit in priority seats reserved for pregnant women, elderly people, or people with disabilities but if there are no priority seats available if you see any disabled person/pregnant women/elderly people standing while you're sitting, you should give them your seat instead. Be sure to line up on the left side of the door on the subway platform, and wait for people on the train to exit before getting on.
