Most of Japanese do not have enough English skill to smoothly communicate. They may understand what you are saying but most of them have hard time speaking. This is due to English education in Japan. The focus of education is reading and writing rather than listening and speaking. Therefore, bring a notebook and pen. Write down what you want to say and they can do the same. It will make communication much easier.
Younger generations (such as under twenties) may have better English skills since studying abroad is getting more popular and English education is changing.
Using Google translation smartphone app will help you a lot as well.