From the xCenta Dashboard, click on Tools > Admin in the top right of the screen.
A new window will appear. Click on Manage Users on the left hand side of the screen.
A new page will appear, click on the 
icon.
A new window will appear, click on the Sites tab.
Click on Add Site Association.
A new pop up will appear, select the relevant site(s) and click Next.
Another pop up will appear. Select the relevant roles and click Ok.
If you are unable to follow these instructions, you may not have the required user permissions. Please contact your Site Administrator.