How to improve your English from scratch saving your money

The English language is fundamental to every technology professional. How to start developing this skill saving money? According to a well-known Brazilian magazine only 5% of Brazilians are fluent in Englishs, it’s incredible how many English schools there are in Brazil and so few fluent people, not to mention that 65% of them say they do not study because it is expensive. I’m not fluent in English, so I’m not part of these 5%, but I’d like like to share some study tips that I used or I use today to continue improving my English without necessarily going to a regular school.