The difference in climate across Australia is huge. Northern Australia is hot and humid, the inner hot during the day and cold at night, while the alpine region can be cold, wet and windy or even snow covered several months of the year.
It is therefore imperative to be well prepared for the worst conditions which may arise.
I've created a list below of the gear I generally pack on any extended hike. When packing you should
consider the weather, season and conditions in which you are hiking. It's better to be over-prepared than under-prepared.
The absolute best way to ruin the camping experience of those who come after you is to leave your shit behind after you (literally and metaphorically). I don't know how many times I've discovered an ideal camp/eating site only to find garbage lying around. Food scrapes will take months to decompose. Ideally, everything you carry in you should carry out (especially if it's not going to decompose). If you just can't stand the thought of carrying your own crap out with you then ensure you bury it. Anything buried should be in a hole at least 15cm deep and at least 50 metres from any water source. Remember, whatever you leave behind, other people are going to find.