The first thing that you need is motivation. If your motivation is strong enough, it will pull you toward your goal of learning English. Your goal could be to go on a vacation to a country where they speak English, study at an American university, etc. You need to find a reason why. Additionally, you need to find materials that interest you. If you listen to music and watch movies that you like, you will be more likely to repeat those activities. I have seen people learn languages studying with teachers and by themselves. I never really learned French because because I had to learn it for work. My motivation was really low. However, when I moved to Colombia I learned Spanish very quickly because I had to learn it to survive and that provided me with very strong motivation. I watched movies and listened to music in Spanish. As well, I played and coached hockey with teams that only spoke in Spanish. I made a lot of great friends in Colombia as well. Overall, I made learning Spanish a very enjoyable experience. The reality is that if you have the motivation and you make it fun, you will find a way to learn. If you are looking for a teacher, make sure that your teacher finds what motivates you and makes the lessons interesting for you.

 Do you mean the formal rules of written English or do you mean conversational aspects such as accent/pronunciation ? 

In my opinion, the best way to learn is implied. You only have to go looking for your interests! :)

Recently I've read a really fascinatig article about traditional ways we use to learn english (and other foreign languages) and how we waste our time emloying them. The autor of the article breakes some really serious stereotypes and bias about right ways of learning languages. We were all teached in schools that doing these stupid grammar excersises regularly is the best approach to successed in english. NO. Everything that you shoud do is to LISTEN and READ as much as you can. While listening and reading we get the major ammount of information and build up our baggage of knowledges about the language and the vocabulary and then to test yourself you may try to speak. Speaking is the best way to find out whether you go on the right track .