Simply download the NightOwl app available for both ios and Android, login using Facebook or an email address and spin the wheel to win.
Every spin wins and some of the current potential freebies include:
Frostbite (Frozen Coke)
V 250 Gnarly
Cool Ridge Sparkling Berry 500ml
Barista Bros Iced Coffee 500ml
Bundaberg Drinks range 375ml
Dare Iced Coffee 500ml
Promotion is running until March and you can spin every day so enjoy :)
EDIT: You have to claim the prize within one hour of spinning. If you don't claim within that time the prize is reset and you can just spin again. If you do claim the prize you are locked out until the next day before you can win again.