what car are you going to be driving?
will you be towing a cravan? or sleeping in a swag/tent or even motels etc?
Id make sure i had a land-cruiser or similar with a big fuel tank
Bull bar, Good quality CB radio, extra fuel, lots of water and food, maps and tools incase stuff goes wrong and you're on your own
you have to plan how long you intend on going for, that way you can plan a particular route, roads etc
and also pack enough supplies
let people know where you intend on going and when you expect to arrive at certain places before you set off. Makes it easier for people to find you if need be.