What is the best way to revise for English exams?

Two Main Ways: Comprehension & Application
1) Comprehension
-Involves creating organised, coherent and clear notes from which you can learn far more easily
-Make these notes in whatever form suits your learning style best (flashcards, mindmaps, handwritten notes etc)
-If you're unsure which revision method suits you best, experiment with a variety to determine your preference
-Right or wrong, exams revolve a lot around memorisation, so learning these notes by heart is a non-negotiable
2) Application
-Simply learning notes isn't enough however; you need to practice applying this knowledge
-The best way is through past papers (easily found online - I will find these for you if need be)
-You can also ask your teacher for practice questions in the same format as your real exam questions
-Do these papers/questions under time limits to familiarise yourself with exam timings and pressure
Extras:
-Additional reading on your subject certainly never hurts, even if it isn't required, as it will increase not only your knowledge but also interest in the topic, making you keener to revise it (e.g. if you were studying a play by Arthur Miller, perhaps you could read his autobiography in your spare time to supplement your understanding of the origin, context and meaning of his play)
-Listening to relevant podcasts and/or watching relevant films/documentaries/YouTube videos will also help you immerse yourself in the subject and be all the more prepared to do an exam on it
Remember: the more you prepare for an exam, the more confident you'll be in it, and the more confident you are, the better you'll do ... success is in the preparation!