This action can be performed by any user with the rights to create new users.
To create a user:
Select the contacts icon on the top right and side of the page, then select "Manage Users" option to view all the users within the organization.
Select the "Create New" button.
Then key in all the relevant details as requested. Ensure to check the relevant boxes for the user access and then click "Create"
The user will then receive an email notifying them of their username and how to set their password.