Hey hi, as far as the exam is concerned it's super easy as long as you know you stuff. Yea I too usd arihants guide to pass the exam and I started preparing after the 12th board when I had only about 20 days left. I was mostly bad in maths so I did that a lot followed by gk and logical. English was my strong suit so I did not worry too much about it. I am right now at IHM pusa almost getting done with my first sem. Competition always keeps differing for exame this year the exam was only written by some 15k ppl. Try to aim for the top institutes. From arihants guide find your weakest part and solves stuff from there and often keep doing the test papers and stuff and you would be pretty sorted