Format a fact - Caption and Styles
Changing the caption
To change the caption of a fact, click on the Edit Fields button on the Home Tab > View Ribbon
Select a Fact and change the caption. Click Save after changing
Changing the Style
Change the style of any Fact (or the whole cube) click on the button on the Home Tab > View Ribbon . First create the required style, and then apply it to the required fact.
For details, refer to Format a cube - Using Styles