Getting better grades in maths and physics A level

Hi, I am a year 13 student doing maths and physics a levels. My current grades are around Ds but I want to get mch better grades then Ds in my A levels. I struggle with these two subjects and I do not know how to revise efficiently to get the grades I need. I have started using past papers but I know I am not being efficient with them because I get overwhelmed by them and then don't have the energy to mark them. Any tips on how to revise for maths and physics a level in 5 months and increase my grades?

I haven't done A Level Physics yet, but for Maths it's usually down to practice specific types of questions and past papers.

I think I have done 20 papers before I did my exam.

Your attention in your maths papers should not be in what you did right, but what you did wrong. You would be surprised by how the little things can add up (especially if you're doing EdExcel). I sometimes look through the mark scheme to figure out where I went wrong with my approach and how I can do it better. If you are wondering how the examiners got the answer as they are in each step, it means you're learning (you need to think through this).
After reviewing the specific question, I would try to redo the question using the new approach (if applicable) until I got the question right and score full marks.

If you don't understand the approach or get anything about the question, then this highlights the need to revise this specific topic. I would then use the revision guides to go through the material and go through the questions at the end of the page/chapter to get the full swing of it.

If you have exam practice books (different from revision guides), so much the better, Unfortunately, as far as I know there are only 2 companies that publish exam practice books for A Level maths: CGP (I don't particularly like them) and the exam board that you are with.

If you haven't done so already, you should have completed the syllabus ahead of time (ideally by the end of the month) and then spend the remaining time doing practice papers and questions.

Maths at A Level is more or less a very methodical problem solving subject. The hard part is thinking the problem through under timed conditions (believe me when I say I managed to figure out half of the answers from questions I was struggling with after I have completed the paper). The techniques and methods are usually the basics i.e. they are tools; to get the marks you deserve, you need to be able to figure things out and think in a particular way to get more marks. Tools are only useful if you know how to use them.

There are also a number of YouTubers who scored A/A* in A Level maths who you can refer to:
https://www.youtube.com/watch?v=pM0_0E3sV-8
https://www.youtube.com/watch?v=010HGihy0eM
https://www.youtube.com/watch?v=65xy8QuGH7k
https://www.youtube.com/watch?v=VqAX4Ui_9lE
https://www.youtube.com/watch?v=ixf8RJp8H1s
https://www.youtube.com/watch?v=KWIWiY5WR_M
https://www.youtube.com/watch?v=3dJqheOpRDE
You will need to search on YouTube for the rest of them. However, they more or less echo the same advice: practice papers.

Good resources that I usually look to for revision material and to go through certain workings include:
TLMaths: https://sites.google.com/view/tlmaths/home, https://m.youtube.com/c/TLMaths
ExamSolutions: https://www.examsolutions.net/, https://m.youtube.com/user/ExamSolutions
Bicen Maths: https://www.youtube.com/c/BicenMaths
Physics and Maths Tutor (past papers if you can't find them on the exam boards' website): https://www.physicsandmathstutor.com/maths-revision/
There are plenty of good sites out there, but you would need to google for them.

When looking for exam papers, use all the papers that you can find for your spec from your exam board first, then proceed to go through past papers from other exam boards. Often the practice questions in revision gudes make things too obvious and are best used for warm ups (things will not be as obvious in actual exams).

The other thing to note is that the % of the paper that you need to get right in order to go from a D to a B or A is not that much more than you think considering the relative difficulty of the paper. This could be the difference of 2-3 questions more at full marks per paper. Each question would be testing 1 or 2 topics of your spec (usually just the 1). If you know which topic it is, you are already half way there.

Everything else is usually exam strategy.