In order words, your basic fundamental understanding of the concepts from PCM should be clear to the core. You may also explore BITSAT preparation books like Arihant's BITSAT Preparation or MTG's BITSAT Explorer. As you can not cover each and every topic from Physics, Mathematics, Chemistry, you must polish the important topics and what carries more weightage for the paper. You must also take a series on online tests and also mock tests. Ideally you should also solve 1-2 papers everyday strictly and try to complete each paper within a time frame of 3 hours. This exercise should be carried out in the last 10-15 days of your preparation. You should also consider the important topics from all the 3 sections given below and should not leave any scope of carelessness in mastering them. Important topics from Physics – Mechanics (Newton’s Laws, Work and Energy, Rotational Dynamics etc), Electrostatics and Electromagnetism and Thermodynamics. Important topics from Mathematics – Integral Calculus (50% of the paper is expected to be from this), Coordinate Geometry and Complex Numbers and Differential Calculus. Important topics from Chemistry – Inorganic Chemistry (Go for NCERT), Ionic Equilibrium, Physical Chemistry (Chemical Equilibrium and Gas Laws) and Organic Chemistry.

All the best!