Read.As much as you can.I too live in a third(or maybe a two-and-half?) world country.You have the internet with enough number of things and articles to read.Start with small novels if you want(Enid Blytons,Franklin W Dixon etc) and move your way up.
I live in a developing country as well. Watch as many English cartoons, shows and movies as you can. Most of the media you consume should be in English as well. Try to visualize the words at the same time you hear them.
learning a language is all about repetition. and listening to podcasts and watching youtube videos -- here i'm thinking of lectures, online classes, and tutorials -- over and over again, will help you pick up new (technical) vocabulary + you have the added bonus of learning, apart from the language, some new concepts and/or modes of thinking.
