Maths is quite formulaic at A level. The formula is
Go through worked examples and theory
Do 10-20 questions, starting with simple easy ones and building up (e.g. odd questions in your textbook)
Go on to next topic
Once done, do 5+ past papers
To enhance your learning, teach other people or answer questions on here. Explain things to others. This is the Feynman technique in action and boosts your learning to another level. I used to help a heck of a lot on here throughout my A levels in Maths/F.Maths, Chemistry and Biology and no surprise I got straight As (A* didn't exist then) - I got more in return from helping others than they got from me, if that makes sense. Partly this is because you're caught off-guard and questions pop up from all areas of the syllabus - some of it that you probably did months ago and forgot. So by thinking about these, you build mental links between different techniques and different areas of the syllabus. It's that holistic view - in every subject - which gets you the top grades, but if you've been doing it throughout your study anyway, it exams become a doddle.