The Hazard Perception Test (HPT) is a practical, computer-based test. However, the theory resources available can still help with your preparation. In the lead up to the test you should revise the Hazard Perception Handbook produced by the Roads and Maritime Services and the summary of this content provided by Driving Test NSW. This handbook outlines the skills necessary for effective hazard perception (what the HPT assesses). Reading through the Handbook and revising with the summary (which condenses and synthesises the 92-page Handbook into 22 pages) forms the base for an appropriate preparation for the HPT.
To get an idea of what the test will look like and how you will interact with the touch screen you should avoid the practice modules provided by RMS. These modules do not simulate the real test and are not particularly helpful in preparing you for the HPT.
Luckily, the South Australian version of RMS has a handy resource that simulates the test very accurately. Some of the clips they use are so similar to those in the real test you could easily argue they are the same footage. There are 5 practice tests, each with 7 questions for a total of 35 questions.
This is the number one (and essentially only) resource to practically prepare for the HPT. You can find links to the practice tests and Driving Test NSW commentary on the appropriate responses here.
Check out the other resources available to help you pass the Hazard Perception Test so you can take the Practical Driving Test: