Dear Aspirant,

CAT is not the type of exam which requires you to study for 8 hours for one year but studying for 3-4 hours for 6 months will be enough to bell the cat. Since you are in second year of your graduation your primary focus should be on your graduation marks. Your grad marks will play an important role in your admission in to IIMs. You could give multiple attempts at CAT but only one at your graduation.

So you should focus in getting good marks and also try to explore more sides of you as you're in middle of graduation. If still you find that CAT is the thing for you then I suggest you should start preparing for cat after completion of your pre-final year and you can give CAT in  your final year. The exam took place in week of November every year.

Hope this helps. Thank you.