Meet as many smart people as possible: If you are not in the top notch schools you don't get to see a lot of them. And even when you make it into the best ones chances are that half of the class is not that intellectually simulating. I mean they are great at there course work, sure, but don't really want to think of anything else.
Study Subjects that are new and challenging: Indian colleges do not follow the choice based credit system. It's the college's way or the high way. Although there are 2-3 subjects per semester you absolutely love, the rest offset the fun by loading you with things you are not interested in.
Another point, most of the engineering students in India do not want to be an engineer. They want to get into a good MBA program.