Well adibond u can try few things ...

Firstly make it a pact with ur freinds that u'll communicate with each other in English and only in English. Dont feel shy even if ur communication is poor in the starting. This exercise will surely enhance ur confidence and fluency. Just make sure u dont revert back to hindi in 2-3 days. COntinue this exercise for atleast 2-3 weeks.

Next mantra is that practise makes a man perfect. So give mock interviews to ur freinds, teachers, uncles & aunts etc etc. The more mock interviews u give, the better u'll be able to present urself to the interviewr.

try these two for starting, u'll find these two exercises really helpful ....