Dear Friend,
If you want to master grammar and composition, get hold of a copy of Wren & Martin - the authority on the subject - and attempt to complete all the exercises.
Earlier, people used to read "The Hindu" for its flowery language, absence of errors, and apt usage of words in context. Though its content quality is not what it used to be, selecting articles like the editorial is worth reading regularly for vocabulary improvement.
For vocabulary enhancement, I strongly recommend Anu Garg's 'A Word A Day (AWAD)' available at Wordsmith.Org: The magic of words. This is described as "The most welcomed, most enduring piece of daily mass email in cyberspace" by The New York Times.
You can also try reading English novels that suit your taste. These will improve your reading and writing skills.
For fluency, you can listen to BBC Radio Channel, English movies, and English programs aired on television channels like AXN and Zee Cafe. However, the most important part is to express yourself in English each day for at least 5 minutes. Before retiring to bed, you can speak about what you did that day!