The Diary TV displays a content page/slide after it displays the diary sessions.
The content displayed on this page is editable by the Manager user on the system.
Text content or images can be displayed.
Go to TV then Edit Content:
You'll arrive at the content editor which may or may not already have content:
The best way to display attractive content is to create actual graphics in another application and upload it using the Choose file button (A).
For simple informative text content, you can just click on the top left of the content area (B) below the Choose file button, and enter normal text content.
Use the formatting options to centre and decorate the text as needed: