Find someone to study with.
When I was studying for my exams, I got my mum to read out what I had to learn and then ask me questions on it, I did pretty well, I got mainly As and Bs.

But you could even find a friend who has to learn the same stuff as you, they can help you with the stuff you don't understand and you can help them.
I find talking about a topic helps me memorise it better.

Hope that helps :)

Take your battery out of your laptop/phone/device, or your power supply out of your PC. Only plug it back in when you're content with the work you've done.

Aderol