Useful tips? Planning to move to Japan

I'm a 14 year old British student at high school. I seem to be picking up Japanese quite fast and am good at pronouncing words and reading kanji.

What tips would you give me?

I'm planning to become a English/Art/ICT/History teacher.

What sort of tips?

The most basic ones are:
1) Make sure to finish university and get a bachelor's degree.
2) Visit one or twice to try to get a grasp of what the country and culture is REALLY like.
3) Realize that the beginning levels of Japanese are extremely easy and that it doesn't mean much. It's when you get to the more difficult levels where you realize if you're really good at it or not.

One tip- if you want to teach anything but English in Japan you will need a degree in Education so that you can teach at an international school. Teachers in Japanese public schools must be Japanese citizens.

1. Become very fluent in Japanese, i.e. speak like and write like Japanese. This is a must if you want to make a good living and not just teaching English
2. Finish College. Get your Education first. Deal with the reality part first.
3. Save up tons of money before even considering leaving your home country. You may not be able to find a job for a while, so you need to prepare for the worse
4. Start off with doing short term homestays before you actually move to Japan. That will help you learn the customs and minimize the cultural shock that you will experience

I missed out the part you want to be English teacher. But my tips I gave you still apply, since the better paying jobs would require good Japanese abilities.

One important tip I forgot...

5. Networking. Find a way to know locals before you come. They are good resources for survival. Make penpals or do language exchange in your home country.