Invite User
Select the Users icon on the left.
Select Invite User from the sub-menu.
Enter the user's email and select a Permission level.
Select the Role of the user.
Enter the user's first and last name and click Invite.
You can also send new invites from the Manage Users page.
Pending invitations will appear at the bottom. The recipient of the invitation will receive an email notifying them of the invitation.
Here is an example of the invitation email a user will receive.