The biggest thing in the exam is not to worry.
It might be worth just reading that final question first, before starting the first question. Some people would do the esssay question first but personally i would prefer to do it at the end for various reasons. The questions at the start will give me time to think and plan what i am going to say and i would be thinking about the time i had spent on the essay question and time spent needed for the others.
If you have the time it may be worthwhile creating a dreaded plan, doesn't have to anything major. Even if it is just a few topics and areas you want to talk about whilst writing so you don't forget anything.
Aside from the essay question if you are consistently getting a certain bit wrong then
provides a good question bank and answers separated into topics. I haven't looked through all of them but some of them could be legacy so whilst still valid may introduce concepts no longer on the spec.
Or if you want some notes you could check here
Oh and 've got hold of this booklet, haven't looked through all of it yet but it looks pretty good