What I do for preparing of cat

Hello Shivam. I would recommend you start reading quality newspapers/editorials. This would improve your ability in understanding longer passages, and can help you in paragraph formation. Just by doing this on a regular basis, you can improve your scores in verbal section drastically.

For the reasoning and di section, start solving puzzles. Along with puzzles, also try and improve your calculation skills, by calculating different data in a economic report which has graphs and other charts. You can solve sudoku on a regular basis, to improve your skills in reasoning section.

For quantitative ability section, just go back to class 9 and 10 maths books. Solve the questions and clear the concept. Just by doing this, you would be able to solve at least 75% of the questions in this section.

All the best.