About the most efficient way to get ready for GCSEs

I am currently undertaking 10 GCSE subjects (Zone 4) and I have staggered to achieve success in O1. I have to appear for 4 subs in the coming year and I have no idea how to prepare myself.
I usually make notes because I am a firm believer of the fact that what the hand writes the mind remembers but note making has become kind of redundant at this point, what is a better approach to learning (besides the obvious option of solving past papers)
Does anyone have any suggestion?

Do some research or study a bit of the courses so you aren't taken by surprise when you start your subjects in september.
Seneca offers some good foundation/grounding and look at some yt videos on your subjects to get the gist of it.
Don't over-prepare (as in don't study the entire subject's course, just snippets of it!), I'm sure you will do absolutely fine!

I think using quizlet if you're memorising info is absolutely great - it helps more than you think!
When making notes, I usually just make a summary page of notes for each topic for my science subjects, but I never make notes for things like maths. Try to see if you want to make notes for everything or if you could just watch a video explaining it - it always helps to look for other options if you don't always want to make notes.

I hope that helps and good luck!