Users can only be added by someone with an administrative role.
Go to Settings (Cogwheel) at the top right and click on Users.
Enter a valid e-mail address and choose a username (for example, first name + last name). The User receives an email with an activation link at the specified e-mail address. Click on the link to confirm and activate the User.
Did not receive an email with activation link?
Do you want to send the email again with the activation link? Click on the Pencil next to the relevant User and resend the email. (The activation link cannot be sent again if the user is already activated).
Before a User can log in, accounting records and relevant user rights must be assigned to the User. Read more about user roles and user rights.