These instructions were created on macOS Big Sur but should be applicable to other versions of macOS.
Click the Wi-Fi icon on the menu bar and select the eduroam wireless network.
Enter your ITS username and password in the format firstname.lastname@example.org
Before connecting, click Show Certificate to review the security certificate is valid.
The certificate should be issued to warwick-wireless1.warwick.ac.uk and issued by GEANT EV RSA CA 4.
If the server certificate does not match you should click cancel to abort the connection.
You may be required to enter your macOS password to update the settings on your Mac.