You'll need a smart phone, tablet or compatible device with internet/data access to play. Check compatibility of your device here:
http://www.intercaching.com/intercache/test.php
Go to the parking coordinates then click on this link to get started:
http://www.intercaching.com/intercache/play.php?gameId=1782
At each WP you will be asked questions, but your answer will only be accepted when you are within the 'Radius' of that WP. With the correct answer you'll be able to select and move to the next WP. There are 10 waypoints to collect around the circuit. The final WP is GZ where the cache container is hidden.
Your answers should be in lower case (to keep it simple and consistent).
It would seem that Vodophone coverage may not work well enough, Optus may be just good enough, Telstra works the best.
Enjoy...