You can easily crack CAT exam if you focus on the main domains of the exam. You need to focus on-

1. English

2. Aptitude 

3. Logical reasoning and data interpretation

With this you also need to have practice in writing as you would have to clear written ability test (WAT) in the next step. 

If you have good conmand over these topics you could easily clear the exam. If you will practice it for about 7-8 months efficiently you can easily crack it. Just stay motivated and give it your best.

All the best