All that Kaz3g and CoodaShooda suggest plus..
Please consider carrying a 406 MHz Personal Locator Beacon, preferably registered with your personal details at AMSA. Know how to use it and don't be embarrassed to use it if you get stuck, for any reason. Keep in touch with friends that can monitor your progress. The roadhouses have phones.
There's no reason for properly prepared motorists or aviators to die in the Australian outback deserts anymore. You can never carry too much drinking water!
Enjoy your adventure!