The Australian National Flag was chosen in a competition after Federation and first flown in Melbourne in September 1901.
Since then, it’s sorta been used to represent Australia – the military did fight under the British flag in World War I. And sure, a quarter of the Australian flag belongs to the United Kingdom, and the other main feature is a bunch of stars that anyone in the southern hemisphere can see, and 21 other nations use the same three colours for their flags, but it's ours!
There are many ways to honour for the Flag of Australia. The Flag must not be flown at night except when illuminated, nor should it be flown upside down, or be presented when faded, damaged or dilapidated. So wearing the Flag as a pattern on a pair of brand new silk boxers is quite acceptable, as long as it’s during the day.
Also, make sure you wear as many versions as possible, be they fake tattoos, earrings, stickers, mini flags, large flags and neckties, especially on Australia Day. Especially if you are going to a music festival, like the Big Day Out - don’t let the narcs stop your patriotism!