Dear Jitendra,

In order to prepare for BITSAT you need to start your preparation by NCERT books it will help you to clear your concepts and to build your fundamentals strong. 

After, completing NCERT you can refer to other publication books like Arihant, MTG and Disha. 

Make sure you refer to previous year papers to understand the exam pattern and to know level of the questions.

BITSAT is all about speed so make sure you solve as many as mock test series for your preparation and you work on time management as well.

If you are well prepared for JEE Main you can easily crack BITSAT exam.

All the Best for your Preparation and Exam!!