Your question is like the question 'How can I get slim and thin if I pig out a lot every day?'. There can be other variations of your question - How can I swim without swimming? How can I breathe without breathing? How can I drink without drinking? How can I paint without painting? How can I learn without learning?
The most easy, funny and amusing way is through listening to music! it is my personal experience actually, I have learned "and still learning" English through music. You can gain vocabulary by translating the new words you hear them in the song you are listening to and write it down in your notebook.
That was my vision, hope you all the best :)
dont learn any thing, you will learn nothing.Then you will learn something that is called learning