its all about studying. there is no tablet to get rank in ca or in any exam. instead of discussing "how to get rank" you could have utilised this time in study. this is my opinion. all the very best for exam
finish 100% syllabus 5-6 months before exam. then get yourself disconnected from the world including family. then repeat the whole syllabus atleast 5 times. prepare books of atleast 2 authors for every subjects. and main thing is you must be very intelligent student with extra quality mind gifted by God. then rest will depend on god. for this you can take blessings of your parents.