First to learn English well, you must know your grammar, only when you know how to use grammar, you can improve your English quickly. You can also listen to English tapes or watch Tv programs to improve your listening and also speaking.
Second, remember not to be shy when you speak to other people, they will not make fun of you, take a deep breath and smile when you're speaking to foreigners.
Finally, prepare a English notebook to write down all of the English words that you often make mistakes on. Day by day, i'm sure your English can improve alot!