Add the appropriate NetID under “Add individual members”:
Set the “End date” for an appropriate amount of time to allow the user to set their auto-forward. (It is suggested to keep this under a week.)
Select “Add individual(s)”.
The user will now have the ability to configure their auto-forward. To validate it was set properly, and to an approved domain, run a compliance report for your dept found here: https://wiscmail.wisc.edu/admin/index.php?action=request-o365_compliance. Auto-forward may only be set for approved domains.