Navigate to "Configure" under "Service Desk Reminders".
Set the required project role(s) to view issue reminders. Only reminders for projects where a user is assigned to one of the configured roles are visible to that user.
Check 'Hide Issue Reminders when 0' if you want to hide the issue reminder when there are no issues a user needs to be reminded about.
Check the "Issue Reminders redirect to project queues" field if you want the reminders to redirect you to the project queue page instead of a list of issues. Read more about the different redirection pages here.