The first thing is you must be familiar with the whole syllabus. Now, you will find it somewhat relatively easy to tackle JEE level problems and understand the concepts. Read the prescribed books by reading the concepts thoroughly and going through each and every problem. Try to build a firm base of concepts on the basis of problem solving. IIT asks questions to test your concept understanding not to test your formula knowledge. I will recommend these books:
· Concepts of Physics by H.C. Verma
· Problems in Physics by I.E. Irodov
· Fundamental of Physics by Resnick, Halliday & Walker
Concepts of Physics by H.C. Verma is a complete book in itself, you can leave all other books and concentrate on just this one and be sure to get a good rank in JEE. But complete solving and understanding all the concepts is necessary.
· Concise Inorganic Chemistry by J.D. Lee
· Physical Chemistry by P Bahadur
· Morrison & Boyd
· NCERT Inorganic Chemistry
· Higher Algebra by Hall & Knight
· Coordinate geometry by S.L. Loney
· Trigonometry by S.L. loney
· Calculas by I.A. Maron
· IIT Maths by M.L. Khanna
You read books, you get some knowledge and you pass the weekly exams, but how long do you think you can remember the data. You would forget it in a year however strong your memory is. The solution for this is: You maintain three books, one for Maths, one for Chemistry and one for physics. Allot some 3-5 pages(not more than that) for each topic, for example 3-5 pages for Calculus in the Maths book .When ever you study a topic note down the important points in that book, in as small and as legible handwriting as possible. When you are doing some problems you may come across an objective trick, just note down in the allotted pages. This ensures that whatever you read in the two years you have it in some 200 pages i.e you are just writing the summary of dozens of books in some 30 - 40 pages. So when you think you forgot something you need not refer the dozen books and waste time, everything will be in those 30-40 pages. One more advantage is that during exam these books will be like your super power. You can refer these books in just 30min and you have all the knowledge you gained in two years right in your memory.