Best advice I can give is to make sure you keep yourself in good physical form. Stay well, sleep early so you're attentive, make sure you take care of your health so you don't end up coughing all over the place four days before the exam like me.
Accounting is a relatively easy subject but it also requires solid sessions of concentration, particularly if the paper is a more difficult one, so you can quickly draw on and apply various concepts to the question at hand. Get plenty of practice (ideally enough to make it second nature, although it may be too late for that, depending) and KNOW YOUR THEORY. Don't just rote-learn it; make sure you understand what it means, how it works and what it's used for. Basically, if you understand the fundamentals and have a good practical foundation, you can answer just about any question they'll throw at you.
It's not complicated stuff, just do it right.