From the xCenta Dashboard, click on Tools > Admin in the top right of the screen.
From the administration screen, click on Manage Site Indexes and Forms.
A new page will appear. Click on the relevant index.
A new window will appear. Click on the 
icon.
A new pop up will appear, enter the relevant information and then click OK.
If you are unable to follow these instructions, you may not have the required user permissions. Please contact your Site Administrator.