Aussie summers are extremely severe – 40°C in cities and much higher in outback and northern areas.
Hats with a wide brim are best, a long sleeved thin shirt will protect most body areas, and a good quality sun cream will offer some protection, however extended periods in the heat will cause rapid dehydration.
Always carry a minimum one litre of water for each hour in the sun as dehydration can still affect you on hot and cloudy windy days, and too many soft drinks will only make you more thirsty.