The system is built-in styles word2016 user-friendly layout is designed, first, first select the text to use, and then click the appropriate style, the second is after the selected style, and then typing, but remember to cancel before writing style text.
In addition to the style library, we can also use the "style" floating pane Application built-in styles
Click Styles ruled the lower right corner of the small arrow, you can pop style floating window
