Practice makes perfect, solving past papers right while learning is the key. Your teacher should model solving exam questions during the lesson, and you should also have answers written by an expert because the mark scheme is not clear enough. I  provide my students with detailed answers for every topic

You don’t have time to read textbooks, you’d rather practice past papers instead. You need notes that are up-to-date with the latest syllabus, they should be straight to the point without extra information that you wouldn’t need in the exam. I designed my notes around exam mark schemes so that they're highly reliable. Students love to study from my books because they're written clearly with illustrations that help to remember the content 

You need to check your understanding with regular quizzes, which can be done with automated multiple-choice questions that I provide for each topic. You still need to practice the written answers, which count for a larger percentage of your exam. This can only be done with the help of a teacher who is an expert in exam marking techniques. I provide my students with model answers written by me. Students can also reach out to me via WhatsApp or email to show me their answers