I would say it doesn’t really matter if you have a wallet, or a folder, but it is a much easier to find things easier in an organised folder, than in a wallet where you need to take things out first.
I would say make concise flash cards that correspond to every topic, and mark them so it’s clear which ones you will need for Paper 1 or 2. The same with notes, put them in the correct order in your folder. And really just do past papers, because they really show where you have gaps in your knowledge, but really do them in a way that you would do an exam in school. For English just get used to writing essays, plan them and get your teachers to mark them if you can. As to the other subjects don’t make flash cards about information that are obvious to you, because that just a waste of time, and will set up a mindset that you aren’t learning anything useful.