There are some important topics which 'll help you in your preparation-
1-Physics : It's all about coceps, so understanding well and keep practicing of your problems.
2- Chemistry: Its based on numarous chemical equation and fomulas so markup every important point it'll helps you in your revision.
3-Biology: its very intresting subjects based on various concepts theories most ipmortant thing you have to understand the diagrams . You can check some good books for clearing your doubts so that it becomes easy to solve your problmes.