Adding a WordArt is a quick way to make your text stand out. After adding the WordArt, please see below to change the fill and outline color of the WordArt:
Step 1: Click the WordArt, you will see the Shape Format Tab appears in the Ribbon;
Step 2: Click the "Text Fill" command from the "WordArt Styles" section to fill the text color;
Step 3: Click "Text Outline" and select a color from the list to fill the text outline.