Hi matey, did my skills test in July. Best advice is don't worry, I was just the same as you, fretting over every detail. Basically as long as you don't kill the examiner you will be OK.
You'll get a diversion on the second nav leg, probably to a disused airfield or some pokey little GA place, your seven mile thumb and a rough estimate of heading bringing any wind into account will do, you'll find it. Then you'll have the general handling and then rtb for the usual circuits. It's nothing you haven't done and when you've passed on Sunday (weather depending of course) you'll be posting 'I don't know what I was worried about' but good luck anyway.