Adding an online connection to your Office, Word etc 2016

I was looking for a way to add my (federated) login to a Office 365 environment in Word 2016 on Mac. Found out it was hidden in a spot i was not looking. To add an account to an online service:

• Open Word (or Excel, Powerpoint, Outlook)
• Go to File, Open
• Click Options (lower left corner)
• Click Online Locations
• Click Sign In (top left)

Phew....