Set alerts for an event in Calendar on Mac
Be notified of an upcoming calendar event by setting one or more alerts. An alert can display a notification on your screen, send an email, or open a file.
In the Calendar app on your Mac, double-click or force click an event to view event details, then click the event’s time.
Click the Alert pop-up menu, then do any of the following:
Choose a time or day.
Choose Time to Leave. (This option only applies if you added a location. For information about how time to leave is calculated, see Add a location.)
To customize the alert, click the Alert pop-up menu, choose Custom, then choose any of the following:
Message with sound: Displays a notification on the screen and makes a sound.
Email: Sends you an email.
Open file: Opens the file you choose.
To add another alert, place the pointer over the Alert pop-up menu, then click the Add button .
You can set only one alert for Exchange events.
To remove an alert, click the Alert pop-up menu, then choose None.