I just wanted to say: congrats on finishing your Bio exam!
Okay, I'm totally jealous right now that you have a puppy! My parents won't let us get one.
You've got to show us him!!
That's also great that you have oodles of time to work on your app!
I'm not an expert at chem or anything but the below helped me and so hopefully they help you too:
- Practice questions are honestly the way to go for this application-heavy subject! Doing questions, especially difficult ones, will force you to think in more lateral ways and this will really help you to tackle those really complex questions that you face. Also, practice questions were a great diagnostic in helping me identify what I needed to work on.
- Drawing concept maps really helped me link all the AOSs together and it also allowed me to see what gaps I had in my knowledge.
- For the fuels stuff: I found that writing a list of advantages/disadvantages/ for each of them and constantly reading over them really helped me answer those questions in the exam.
- Making an error book. I wished I had done this throughout the year but for exams, I made one and it helped me become more aware of my mistakes whenever I was doing exams. For example, I always made mistakes with converting between units for calculation questions, so whenever I came across that question in the exam, I would think back to what errors I had made (in the past) and made sure to not make them again in that specific q.
- Teaching someone. I taught my brother some of the content and it really helped me solidify some of my knowledge + identify gaps in my knowledge so that was useful (although, he wasn't really paying attention)