If you have less than 60% marks in 10th then I'm afraid you won't be eligible to sit for the IPMAT exam because that requires a minimum of 60 percent in both 10th and 12th. But it's not a very big problem. If you are targeting IIMs you can still achieve that. Just do well in 12th, get a brilliant score in graduation also. And after that do well in CAT, you can surely get a call.

Over and above try to maintain a good profile by participating in national level competitions or doing some courses. That will help in your final selection.

All the very best