Get a good night sleep before the test, no alcohol. No heavy meal before the test either, nor too much coffee.
You'll be more alert that way.

Other than that, try not to maul pedestrians and cyclists. Examinators frown upon that.
And if you have a chance, explore the area where you'll be testing, so that you have an idea of where the one way streets are, and the sneaky situations where you can easily make mistakes.