1. Click on the gear in the upper right-hand corner of the window. Choose Setup from the resulting drop down.
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2. Enter ‘Users’ into the QuickFind box and click on Users (circled below). 
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3. Click the New User button.
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4. Enter all of the required information for the user account. Other information (Title, Phone, etc.) can be added if desired but is not necessary. Please note:
Username will prefill with the user’s email address.
The User License will determine which profiles are available to choose.
If the user needs access to Campaigns, the Marketing User checkbox will need to be checked.
5. Click Save.

6. Click Edit Assignments to add user to the appropriate Permission Set(s) if necessary. Image Placeholder