Lets talk about TED. I love this format because you get to watch and listen to the presentation in your own time, you get to read the transcript, or a summary of it, and then you get to talk about it, to express your opinion, to explain why you agree with certain points and why you disagree.
So not only are you exposed to a well presented piece of English with correct grammar and pronunciation, you now get the chance to speak about it and to add your own experience to the discussion.
By having a large piece of interesting English material that you can refer to every day whenever you have a few spare minutes, you maintain your awareness of the language and you practice thinking in English. Thinking in the desired language is one of the most important steps to becoming fluent.
So attend the Group TED class on Thursday evenings, or book a package of lessons and do a series specially tailored to your own interests - just do it !