What should a non-genius student do to get a seat at IIT Kanpur CS?

It’s good that you have a target in your mind and aren’t leaving everything to luck. The best way for a non-genius student to get a seat at IIT Kanpur's Computer Science program is to work hard and consistently. Rather than stating the usual; solving previous year question papers, joining good coaching institutes, coordinating school with coaching classes, and self-study, I will talk about some of the most basic things that people often undermine 

• Whenever you feel you are falling into a slump, remind yourself that there are hundreds of students who want you to fail in order to grab your position. Remind yourself of this continuously and you will find yourself out of that bubble.
• It’s important to assess your own abilities and be honest with yourself rather than being overconfident. I have seen people who are confident with their academics end up with poor grades. Don’t undermine yourself but don’t even overestimate yourself. Remember you are surrounded by geniuses.
• Don’t get addicted to useless stuff and activities that waste your time. Instead, go for a walk or read for a break.
• You should have prepared yourself mentally and physically for the sacrifices you have to make and the efforts you have to invest.
• Study books that make you understand the concepts in a simpler manner yet give you a comprehensive understanding.
• Motivate yourself with the possible outcome and the reaction of your family. Keep yourself reminded of the happiness and success will harbor.

I would like to end the answer on a final note: There are no non-geniuses, just bad students who do not pay attention in class and bad teachers who do not teach well.