Mike,
Try to arrange for a beer with the examiner a day or two before your test - he might give you some clues about the specific things he looks for.
Apart from that:
1) Don't do anything dangerous. Remember, when doing circuits, you can always go around, and you will not be failed for doing so
2) The PFL is the only thing that's vital to get right first time - everything else, as long as you can recover from any screw-ups, you'll get another go at
3) Pass first time!
Seriously, relax and enjoy it. Your instructor wouldn't have put you in for it if he didn't think your normal standard of flying was good enough, so you have nothing to worry about .
Good luck!
FFF
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