First of all believe in yourself & you are capable of perusing everything.
Practice practice practice this is the only method to increase your skills.
In order to remember important equations used in physics & maths, write them using colourpencils in a white paper& paste it on the wall of your room.
Always study everything by understanding.If you have any doubt just ask it here .
Remember,if your basics are strong ,you can understand & solve any problem.So always remember basic equations
As i said earlier , there is no easy way other than PRACTICE to success. Practice makes man perfect.