Use the specification as a checklist to guide you on what to study and what is not relevant  Textbooks contain extra details that are not required for your exam. Make sure that you only learn what is needed from the specification

I usually see students gathering information from different resources and making their notes

Don’t waste time on this,  you’d rather invest that time solving past exam papers

You still need to write a few notes, try to find ready-made notes that fully cover your syllabus and annotate them with your thoughts 

Don’t leave the past papers until the end, solving classified exam papers while you’re studying, preferably after each section. This will enforce your learning. You also need to develop the skill of writing long answers, which must be developed early before your exam. This is what I have done for my students, I classified exam questions for each topic and solved those questions

Memorisation is part of learning biology, you’ll eventually learn all the little details if you keep solving past papers. So, do not waste time trying to memorise at the beginning,  focus on understanding the big ideas first

A-level biology can be tricky especially when it comes to practicals, you probably didn’t have the chance to do all the core experiments required by your exam board. Try to find a series of lectures to clarify the content. Those lectures have to be specific to your syllabus, otherwise, you have to collect the information from  many different resources which is a waste of time

You have done the notes, solved classified questions, and eventually, you must solve full past exam papers. Start with old papers (those are relatively easier). Solve first with an open book starting with 2019 papers (those are the first papers in the new syllabus)

If you have enough time then start with 2016 papers but ensure that you cancel questions from the old syllabus

When it comes to the last 3-4 full exam papers you need to pace yourself to finish on time. This is one of the most critical issues when it comes to biology exams, many students know all the answers and yet do get the chance to reach to the end of the exam paper. Your target should be to finish the exam paper and have 10 - 15 to revise your exam paper

Bookmark or highlight your mistake while solving full papers, this will become your last-day revision sheet, it’ll have to improve weak points and give you more confidence

Mark your answers after each paper. Don’t be lenient while marking, examiners are quite strict, and you really need written answers to compare your answers to. Check my solved exam papers, I have basically solved almost every exam paper and classified those for each topic

One good exam technique is to write up all keywords related to the question in pencil and then write a statement about each keyword. You need to write more statements that what the question is asking for, this will ensure that you are covering all the mark scheme points. Ideally, if the question is for 3 marks you need to write 4 or even 5 points