Whenever am low I just listen to this song through my earphones and start singing along softly. I have listened (and sang along, obviously) to it so many times that I literally know every lyric of it by heart. But I never understood every line of it. So thanks to Google and surfing on strange attempts of translating it, I ended up on Irshad Kamil's official website, with his very own translation of it. I believe he is currently one of the finest lyricists in the Hindi film industry at the moment.
Anyway, coming to the point, below this paragraph is a version of the track sung by myself. Not a professional, but an amateur's attempt at singing, as I always mention to you. And if you scroll further, you'll find the lyrics and the translation by the lyricist himself, which is amazingly good too. Thanks in advance for leaving in your feedback in the comments section. Cheers!