i got six 9s (bio, chem, physics, rs, geog, history), one A* (business) and four 8s (maths, french, english lit and lang) when i did my gcses last year.
i would say you need to be aware of your own UNIQUE method of learning and how you best remember information, and put this to practice when you take your mocks so that you can alter your techniques for your real gcses and hopefully finesse them.
as a guide, here are my tips based on my experience and what i would have done if i could go back.
1) gcses are a MEMORY GAME: learn the bare minimum required and you WILL get the top grades, it is as simple as this. this is especially true in the content based subjects like the sciences and humanities (the ones i did best in), so LEARN THE SPECIFICATION (this is your bible) and nothing else.
2) use ACTIVE RECALL in as much revision as you can: you need to be actively trying to recall the information and not be passively taking it in by reading, as this is not what you would be doing in the exam. try the technique of blurting, google it. i didn’t do exam questions (ran out of time and there were few past papers at the time) but DEFINITELY do practice questions as this is the best way to test yourself.
3) for ME (i am not endorsing this at all but this worked for me, as i have a v good memory naturally), i would wake up at 4am on the morning of my content heavy exams and just go through all the information (for AM exams), and wake up normal time for pm exams and do the same. if you KNOW cramming works for you, do it.
4) don’t be lazy: I was lazy in maths, I could’ve easily gotten a 9 if I had bothered with practicising skills but I focussed on my other subjects because I knew I would be fine even if I didn’t revise. but TRUST ME, it feels pretty bad to get a grade back that is lower than you wanted because you didn’t put the work in, same goes for English lit/ lang. you need to push yourself because it will be worth it in the end.
I can’t think of anything else rn but good luck! just work as hard as you can and there’ll be no way that you’ll feel unhappy with whatever grades you end up with.