Agree with Extremelyboreduser, and as discussed in another recent thread, it’s essential to cover the gaps between 5.2 and 5.3. Learning maths is foundational - if you have gaps, you can’t build your understanding effectively.
I believe I might be qualified to answer this as I missed half of my year 10 schooling and am now actually ahead of my cohort. For context I went back halfway through 2021 into 5.3 not knowing how to graph a linear equation.
What I did was just grind Khan Academy 1-2 hours pretty much every day I could, of course there are other resources that you could use but this worked really well for me as it followed a logical order which would fill in my absent knowledge as I went. I made the choice to do Advanced and Ext 1 maths to really push myself and so far all seems well. The work is pretty easy for me now with the occasional question I may need help with.
so apart from my rant what I'm getting at is to just make sure you are confident with EVERYTHING. If there's something that you know you aren't the best at then review it until you feel confident that if it came up on an exam it would be easy marks.
Study the content ahead of school so you can get plenty of practice. Also have a mistake book to note down all the mistakes you made during homework of past papers and make sure you don not make the same mistakes again. Do not memorise maths content or just cram a bunch of questions, actually understand the content and concept behind each question and formula/concept.