Starting in Tokyo, name the largest city in each direction. Then continue in the same direction for the next largest city. For example, for north, you will name the largest city North of Tokyo, then the largest city north of that, then north of that, etc.
Going north and south is simple. But going east and west, you can go around the globe many times. Isn't Guangzhou the largest city both west and east of Tokyo? If you mean west/east but not crossing the date line, you should perhaps say so?