When you first sign up to RedHotPie, you can select your location by either typing the suburb/city in the Location box and selecting from the drop down menu, or by turning on your location settings.
If you wish to change your profile location at any stage go via the App, click on the circular avatar of your main profile photo on the top-right corner. Click on Edit Info > General Info > Location > Type your new suburb/city in the box and select from the drop down menu, or click on 'Use my current location'.