The Personal Timetable is an Opt-in calendar subscription service that presents your Class Timetable and Exam Timetable on your mobile device or desktop calendar app.
The Personal Timetable settings are managed via this myUNSW page. This includes creating or suspending / reactivating the service, and any other options that are applicable to your device. The link is located under "Online Services" for both Students and Staff, on the left-hand side menu for "My Student Profile" and "Academic Admin" tabs respectively.
Your personal timetable is compatible with most device calendar apps and UNSW provided email / calendar clients. Here you can access guides for accessing the timetables on your device.