Hi Bevin,
The most important aspect regarding your subjects is understanding the definitions.
I suggest that you mind map only the bold definition. It would be best if you use your own words to define them after you have understood them instead of copying word for word. If there are some definitions you are not able to rephrase, add some of your own associations of yours.
Use pictures - physics especially, Draw apples falling down, draw a lightning passing two points. Draw cars colliding.
For chemistry - draw bottles, molecules maybe even as if they were alive. Draw them with eyes and legs. Use fun stuff.
Use your own associations. I remember when I started this some time ago and learned physics. E=mc"2" I visualized a Mall and two doors - enter and exit on top of which there were lights. :-)
