When it comes to the things to do in Japan, most travelers have a list of major sights, shrines, parks, gardens, restaurants, and museums to explore, but Japan's unique culture is an attraction in itself and simply being immersed into the unfamiliar is the best experience of all. Upon getting lost frequently, no set planned agenda, it was an awesome experience to see the culture and the extremely humble Japanese people. It was difficult to get around because of the English is far and few, but the humbleness of the people when asking for help was incredible, as they tried to help with their minimum English as much as possible.
I stayed in Shinjuku, one of Tokyo's downtown areas. I like it for just wandering around and people-watching. There are lots of shopping and nightlife and a big park called Shinjuku Gyoen that’s cool to stroll through.
Don't miss Meiji Shrine. Meiji Jingu is one of the Japan's most popular shrines . In the first days of the New Year, the shrine regularly welcomes more than three million visitors for the year's first prayers, more than any other shrine or temple in the country.
The shrine is surrounded by a forest that covers an area of 700,000 square-meters, which consists of 120,000 trees of 365 different species, a forest within a city. Take a stroll through Yoyogi Park, which is adjacent to Meiji Shrine. Yogi Park has a variety of landscapes, from lawns with ponds and fountains, to flower gardens, to shady forest groves. From Shinjuku take the JR Yamanote Line direct to Harajuku Station.
If you have time and to expand outside of Tokyo, then go to Kyoto. It is noted for traditions and temples. It is charming with lots of parks also. I loved Kyoto much better then Tokyo, as it has a more wholesome feel to it.
If you don't know, Japan has a strict no drug policy, and you will be sent to jail if you are found with any, then kicked out the country and not let back in. This includes pharmaceutical drugs that are prescribed by your doctor and over the counter drugs. So check with the Japanese Embassy and email them about your prescription medications or any medications, if it is allowed in the country and how much.
The last thing you want when you arrive for your vacation is a search by customs and they find drugs that are not allowed and you are set behind bars and then kicked out of Japan. This is a serious matter in Japan and not to be taken lightly. Here is an email to send your inquiry. They are fast at replies, so better be safe then sorry; yakkan@mhlw.go.jp.