In a nutshell, growing trees around your house - particularly ones that provide shade to the east, north and west - will help create a microclimate that is a fair bit cooler than areas that are paved or even covered with lawn.
Plenty of trees native to the Illawarra are well suited to this shading role. One beautiful local tree is the Bonewood (Emmenosperma alphitonioides), which has an elegant shape and masses of orange fruit in winter. I don't have any great photos of it, but this shot of the leaves by Peter Woodard on Wikipedia gives you an idea. You can also see Bonewoods growing on Gipps Road just east of the Keiraville shops.
|Slightly out of focus - seeds of a bone wood|
tree growing in Gipps Road, Keiraville
|Not the greatest shot - Birdlime Tree|
growing in part sun on a creekside.
|This is a baby Lance Beard-heath, showing|
the amazing pale green star shape of the
new leaves as they unfurl. It can grow to 3m.
|Here a Heath-Leaved Banksia more or less|
completely hides two Native Elderberry
bushes. They are all thriving with about
3-4 hours sunlight a day, and just need a
periodic prune to keep them shrubby.
This section of the CSIRO's Your Home Technical Manual has a few other tips on siting trees and vines for shade, and keeping houses cool with other types of shading.
What are you growing to provide shade in your garden?