It is actually difficult to confidently say what Australian women wear, the climatic condition actually plays an important role in deciding what to wear in Australia, because the climate is not the same all over Australia. The multiculturalism of Australia also plays an important role as to why, the dressing pattern for women in Australia is not the same throughout the country.
However, the little common wears for women in Australia are the same with majority of other western countries because Australian women are fashion freak. But in sub-tropical climate areas, women use to wear cool cotton T-shirts, singlets, Tops. But in some parts of the country with cooler temperature, they tend to wear clothes that give heat to the body like suits, pencil skirts, blouses.
So like I said before, you cannot just attract a particular pattern of dressing to Australian women but so many factors determine what they wear and the determining factor is not the same throughout the country.