Share your calendar in Outlook

Select Calendar > Share Calendar.

Choose a calendar to share.

Select Add, decide who to share your calendar with, and select Add.

Select OK and you'll see the added people with a default permission level.

Choose a name, select the access level to give, and select OK.

Open an email with a shared calendar and select Accept.

In Outlook, select Calendar > Shared Calendars to view a shared calendar.

Choose a calendar to open.

Right click on the calendar's name and select Overlay to layer the shared calendar over your own.