Ive got an Alcatel with a Telstra Sim. Had no problem. They use a different size sim. If you have problems, go into a Telstra Shop, they will fit and check it for free.
Here is how:
From the main screen, press the MENU key.
Tap "Settings."
Tap the "Bluetooth" slider to turn it on/off. When Bluetooth® is on, the slider will turn yellow.
To return to the main screen, press the HOME key.
That should be it.
Hope it helps :)