Answer:
First and foremost, you should know that IELTS is a standard test focused on test your english skills, although in order to get a 7.0 or a higher score it's more important to focus on test prep rather than developing English skills in a traditional way, you must do a lot of practise with official material (there are plenty of books avaible on Amazon), then you must consume media in English constantly and analyse what are your dificulties doing mock tests, and work hard to develop these dificulties