To invite a new user (one of your colleagues) to access your outlet, first click on the ACCOUNT tab at the top of the website before selecting the 'Users' option from the left options.
You'll be taken through to a new screen listing all of your outlets, alongside the list of possible admin rights you can grant any new user. Hover your cursor over them to see what they do. Select the admin rights you would like to grant to the new user and press the 'Send Invite' button to send them an email invitation to join your account.
You can invite as many additional users to your TruRating account as you wish - they will receive an email prompting them to create their own login and password.