How are you preparing for it @ananda_2018
Actually I am student at Cusat ryt now! And for cracking the Cusat Cat entrance you need not prepare separately..just that you have got to be fast enough to complete some good amount of Questions in 3 hours time frame. Just prepare for your jee exams and practice a few Cusat Cat pre year papers 1 week before the exam! That's it! You just don't have to do anything special for Cusat Cat!
One more thing...I have heard that the Cusat cat for this year has been cancelled due to covid pandemic situation worsening...so I am a bit unsure about the whole intake procedure....so you may just see their website for new announcements..(unsure whether the exam is cancelled or postponed)!