If you don’t see the calendar list on the left, choose View > Show Calendar List.
Click Share With, then enter the names or email addresses of people or groups you want to invite to share your calendar.
If you don’t see Share With, click below the last name or email address in the Shared With list. If you see a Shared By [name] list instead of a Shared With list, only the person named can add people.
To keep someone from making changes to your shared calendar, Control-click the person’s name or email address in the Shared With list, then choose View Only.
Click Done.
People you added to the Shared With list are sent an invitation (a notification and an email) to join the shared calendar.
Go to the Calendar app . Click a person’s name, then press Delete.
Stop sharing your calendar with everyone: Control-click the calendar in the calendar list, then choose Stop Sharing.
Stop subscribing to someone else’s calendar: Control-click the calendar in the calendar list, then choose Unsubscribe.
When unsubscribing from a calendar, you can also report it as junk. Reporting junk helps Calendar better identify junk subscriptions.