I am also wanting to improve mine. I have read a lot of articles about this from the Web and commonly they say to improve your english speaking and writing you will need to think english frequently.
To improve speaking, you can do the following:
- Watch english movies.
- Listen to an english radio station.
- Speak english to practice using it.
- Talk to a an american or to a person who knows how to speak english. You can share ideas to each other.
To improve writing, you can simply apply the above mentioned and to read frequently.
These are some of the things that you should apply to your life style and there are a lot more you can do. You can browse the Web and do chat to english speaking people as well.