Preparation for an entrance exam needs to be done seriously. Prepare a proper timetable for study. While preparing a timetable for study allocate sufficient time for study of subjects (Physics, Chemistry, Biology/Mathematics) and also allocate sufficient time for reading, solving of sample papers and revision of study. Try to collect the best study material for study.
Some of the books helpful for preparation:-
• Advanced level Physics by Nelkon and Parker
• Aptitude Test Problems in Physics by S. S. Krotov
• IIT Chemistry by O. P Agarwal
• Physical Chemistry by P Bahadur
• Concepts of Physics by H. C. Verma
• Arihant BCECE Engineering Entrance Solved Papers