Well I'm just adding what I do in practice exams, although b^3's methods are pretty good

First of all you need to ask the "why" questions - why you're making these mistakes - either it was:
- a careless mistake, i.e. you know the answer but you made a careless mistake (something like arithmetic or algebraic errors) - but if you do it again, you can do it
- conceptual error, i.e. you know how to do a particular type of problem by concept, but somehow you didn't see that when you were doing the question - if you do it again, you'll eventually get it after multiple tries
- you can't do the question, i.e. you don't have the knowledge required to do the question, you don't understand it...etc - if you sit there forever, you still won't be able to do it
Personally, after this, I would address the type 3 questions first, again asking what is the reason why I can't do them
- if it's an interpretation that i can't do - then maybe do more extended type questions
- if it's a theory or method that i don't know, then go back to the theory of it in a textbook and do short answer questions on it first before coming back
- also try to think about what you exactly don't get - cause "not getting something" isn't a statement that will help you - you're looking for "i don't get how to do general solutions of trig functions cause I don't understand how to add and subtract multiple integers of periods correctly" (for example) - then you know that you can solve trig functions to get the first two primary solutions, but its the periods thats the issue, then you go back to the theory/examples with a focus on that

Also, rather than looking at your performance on exams alone, it's important to see an improvement with your understanding, you should be finishing each study session with a better understanding of a particular concept or more experience at something than before - it's this gradual change in understanding that will see you do better
I guess that you need to also see that it's not all about practice exams, you can do 100000 of them, but it won't help you unless you learn something from each one, so do what b^3 suggested, try to re-do each question - seeing where you went wrong, or if that doesn't work then do it with the solutions by your side, seeing where it is that you lose track of what they're doing - always a good way to learn
And lastly - how is your usage of the CAS, are you proficient? cause that will have a BIGGG impact on exam 2
hmm, I'd actually suggest that you try to improve your Exam 1 scores to about 90% first - but 80% for exam 2 actually isn't THAT bad

- in fact it's quite decent (might be an A - im not sure)
Anyway, it's a bit to read there, but I hope I've helped out - I'm actually an aspiring maths teacher, so I enjoy explaining and helping - but my parents don't think that teaching is a good career choice - so medicine it is
