Thinking of going October time for a week, need some recommendations and top tips.
I was there in the mid eighties. My strong advice is to be a slightly weird looking young woman**
If you wind up drinking with US marines, don't go back to their hotel room. The corridors have cameras, and it's humiliating to expelled from a service hotel at 3am. Plus nothing is open in Tokyo at that time, so the nuns you are staying with will think you have been murdered. (Ok, so maybe your experience will be different)
Learn some japanese. Even a little well help a lot, and set you apart from the other tourists.
The food is wonderful. It's nearly impossible to get decent Japanese food in the UK, so be prepared for unexpected flavours. It's a delight once you get used to it, or relax into it.
You can buy beer from vending machines in the street, and under 18s don't buy it, because it's illegal.
** I had the weirdest experience in Tokyo. I was there with a large bunch of women of all ages (though not many old enough to remember the war). The group included my friend who I shared a hair dresser with, and looked a lot like me, as well as many other young women. But at one stage a group of students wearing what looked like 19th century military uniforms (Japanese school uniforms are weird) came up to me , and waved their camera at me and asked for a photo. I reached for the camera, assuming they wanted me to take their photo. No, they wanted me in their photo. They bunched around me at took a photo. By the third time this happened, I was used to it. I very much regret not handing them my camera so I'd have a photo to prove this happened. I still don't understand this. As I say, I was with a lot of women, and this happened to me 3 times (at least) and did not happen to any of my travelling companions.
For reference, here is me in Japan.
And here is a bunch of the other people, including my much better looking friend with the same hair cut.