There are some good comments here, but I'm curious if there's any reason you can't take lessons? I would recommend going to your local British Council (or the A

There are some good comments here, but I'm curious if there's any reason you can't take lessons? I would recommend going to your local British Council (or the American equivalent, forgot the name) and try to get classes there. If for whatever reason you can't (too expensive, you live in a place with limited access), then you have lots of good comments here, but IMH(and somewhat biased)O if you want to get a good, professional level of English, you can't avoid classes.