For English Language, just continually do past paper practise
. For Literature, I did mind maps, which sort of had an essay plan on them, and then wrote tons of practise ones! I also made flash cards to learn quotes.
In terms, of other subjects, active recall methods like making flash cards are great for just learning the content- don't waste your time making notes! I also would emphasise the importance of doing exam questions- particularly sciences- I only learned this at A-Level, and I wish someone had put more emphasis on it!
My revision method:
1) Learn the content- photocopier method- write it out till you can recite it- I tend to do this as I make the flash cards...
2) Make quizlet flashcards on the content. Read through the textbook and make questions on everything e.g. What is the role of a nucleus? I have different sets for each sub-topic
3) Learn the flash cards. Keep going through them. If I get one wrong, I type it out five times and "star" it (if you make physical ones, just put it to one side)
4) Then before learning something new, I'll go through the starred flash cards. Again, if I get it wrong, I write it out five times.
5) Once I'm happy with that topic, I do exam question practise. If I get an exam q wrong, I add it to my flash card set.
6) Then just keep going through the flashcards, refreshing yourself. I usually like to spend some time going through something I have previously learned, before learning something new. So, basically in a revision session, I'll spend the first half recapping and the second half learning something new.
Hope this helps
Good luck!