Getting Around in the City
When you don't know exactly where to go it can be exhausting in any city, but getting around in Japan can be an even bigger challenge because locations aren't determined by street names. In fact, there aren't any street names at all! This app offers door-to-door navigation as an upgrade so that's the easiest way to get around, but if you don't have that functionality there are more analog ways of figuring out where something is.
The Japanese way of looking at locations is quite interesting. There's a great two minute TED Talk on the topic that sums it up very nicely (link below). Addresses are written in reverse from largest to smallest.
American-style address: Street Address (# + Street + Floor) > City > State
Japanese Style: Prefecture > City or Ward > Town > District #> Block # > Building # > Floor
As you can see, no addresses ever use a street name. While you may see some street names during your travel, those names are basically honorary (like Omotesando Street), but are never used when inputting an address.
This takes some getting used to, but the main issue you'll run into is that many of the block and building numbers aren't displayed most of the time anyway! As a result, many directions involve referencing other buildings, parks, or landmarks near where you're going.
Additionally, Japanese cities in particular are quite vertical, so interesting shops and restaurants can be hidden away on the upper floors of a building, not just offices or apartments.
Train Station Maps
When you get off of a train it can be hard to know which direction and exit to go towards. There can be many choices, especially in large stations, and taking the wrong one can mean a lot of extra walking. On the train platform you'll see yellow signs listing prominent locations and which exit you should take. Odds are if you're looking for a stadium or government office you're in luck, but if it's a small café it won't be on the list. Then, once you're out of the gates you will often find another more specific neighborhood map to help guide you.
If you're looking for a specific block or building number, especially in a backstreet, there are maps in every neighborhood somewhere along the street, and especially near (and inside) train stations or by police boxes. These are somewhat similar to the maps inside the station, but even for locals they can be difficult to understand so it's best to be prepared!
When all else fails…
ask the police. You can find them walking around sometimes, but the easiest way is to go to a nearby police box called a koban. For most police in high-traffic areas, a big part of their job is simply helping people to get where they're going, so don't worry about bothering them. However, they won't know much about shop or restaurant locations unless it's quite well-known, so having the actual address on-hand is important.
People in Tokyo are generally rushing around too much to notice you, but don't be afraid to ask someone. In fact, in most of Japan you'll also be likely to find a friendly local to point you in the right direction, and if you look lost enough they might even find you on their own for some helpful guidance.