APMIn need of lots of help for September

Hello I was meant to take p5 in Dec 15 and for reasons out of my control I didn't take it. Now I'm sat here with it being my final exam, self studying and panicking. I have no idea how to answer the examiners questions. Has anything changed in those 2 years? Please can someone tell me the best way to pass this beast of an exam? All I have going round my head is what my tutor said when I did a revision course back then of this is the hardest exam you will take.? Does anyone have any good notes/diagrams to help? Thank you