Find some Indian people to chat with and simply practice. Or search for youtube videos of Indian English speakers and watch as many as you can. Soon you will recognise patterns in the sounds they use to represent English sounds that you're used to. And with lots of exposure and a bit of time, you'll get used to it.

What on earth? Here's a news website in "India English" (http://www.mid-day.com/). Let me know what you can't understand.