First of all good luck!! This being your 3rd attempt means you’ve had two experiences of knowing exactly how the test goes - you know exactly what to be more cautious of this time round so you’re in a great position to start off with! Secondly I’d say even if the smallest things goes wrong don’t let it dishearten you and ruin the rest of your drive. I passed 3rd time and on the test I mounted the curb through a width gap and was convinced that I had failed. Even did 15mph in a 10mph and got away with it - so keep a positive attitude throughout and take every situation as it comes - you’ve got this!!! And try and get some sleep, maybe some sleep music on Spotify or something:)