There have been lot of books available and certainly NCERT books have been the best so far, alongwith that you can take up additional resources for solving more complex problems which have higher prpbabilty in the exam.

Some top recommendations by toppers are:

Physics:-

Concepts of Physics Vol I and II by H.C. Verma

.New Pattern JEE Problems: Physics by DC Pandey.

Chmeistry:-

Organic Chemistry by O.P. Tandon

Numerical Chemistry by P.Bahadur

Mathematics:-

Maths XI & XII by R.D. Sharma

You need to give ample mock exams to focus on weak areas, such that you prepare sufficiently with less than 5 months left, atleast 7-9 hours are must for studies alongwith mock attempts every week to gain a good enough score above 250 and for top IITs and NITs.