An excellent fact sheet from the Commonwealth Department of Health and Aging advises Australians to protect themselves from skin cancer by:
Seek Shade
Wear sun protective clothing that covers as much of your body as possible
Put on a broard-brimmed hat that shades your face, neck and ears
Wear wrap-around sunglasses
Apply SPF50+ broad spectrum water resistant sunscreen liberally to clean, dry skin, at least 20 minutes before being exposed to the sun, and reapply at least every two hours when outdoors.