Estimated time: 2 min.
Outlook 2013, Calendar sharing.
In Outlook, go to the Calendar, and locate the “share” section in the top-menu (ribbon).
The marked menus-items below are the ones important.
Let us say you want to share your calendar with Michael Carlsen. Select Share Calendar.
In the “To” – you can search after people, exactly like when writing a new mail.
Find (in this case) him in the address list, and press OK. Remember to select the proper “Details” (depending on how much you want to share. When you select a setting, you find the explanation next to the blue box, just below).
Now you can send the Calendar-sharing, and it will work within a minute.
Should you for some reason have trouble sharing, check that the person you are inviting isn’t already allowed with other rights. Open the “green box”: Calendar Permissions, and locate the person. Remove him/her, and send a new share-invite.