welcome to stasi west australia, page-5

SA has required patrons to register their details at businesses for sometime.
You can either check in to the business using the SA Gov QR code app or use a paper register.

WA will likely be the same.
You write your name, phone number date and time. on paper sheets.
Some places keep a container of disinfected pens and used pens for patrons to use.
Many larger businesses like supermarkets and hardware stores and etc. don't police it so leave it up to customers to comply.