How can I learn English?

It's a big problem to me how to learn English. Because it's a really difficult subject for whoes native language is not English. Using English grammar correctly is essential to us, so is memorizing many necessary words is. But I think if we want to learn it well, it should be like a necessary tool in the social life, not just a language. I hope I can communicate with other country's friends naturally in the future. So I should talk in English repeatedly more and more.