Check your equipment before you go - especially the headsets. I had to do my skills test with the club headsets - which didn't work that well.
When the examiner said 'practice engine failure GO!" I didn't hear him...
then I noticed he was staring at me..
and I said '...pardon...?'
Still passed....
Try and imagine he's your Mum or something - they usually give you the 'I'm an interested non-flyer speech' that means, you can't ask me technical questions on route ("should I be squaking 7000 here..?" , but you can explain what you're doing ("I'm going to set it down in that field there, as this one's ful of rapeseed which is about waistdeep this time of year...").
Good luck mate!