^Agree with nacho, might work for some people.
My advice tends to be a little extreme.
Drink bottles: I usually recommend people avoid them because you want to be using the full 90 minutes as effectively as possible, and wasting 2 seconds valuable seconds drinking water... Never mind, just do what you like

Reading time:
1. Read the answer book first: quickly skim through it so you have an overview of what will be on the exam, what prac you have to do, what the prac-to-theory ratio is like etc.
2. Read both in conjunction.
3. See if you can start answering questions in your head. It's enough to just be like: "Bad debts in the GJ, huh? Well that means I have to DR Bad Debts and CR Debtors Control and Debtor - ." Once you've thought about it once, when you come back to it, you'll remember and be able to write down your answer really quickly.