How to Apply a Theme to a Word 2007 Document
You can apply built-in and custom themes to your Word 2007 documents. Because you can use only one theme at a time, choosing a new theme replaces the current theme.
Click the Themes button.
It is located in the Themes group on the Page Layout tab. After you click it, the Themes menu appears.
Point the mouse at a theme.
Word shows a preview of how the theme would look if you applied it.
Click to select a theme.
The theme is applied to your document.
You can remove a theme by choosing the Office theme or the menu command, Reset to Theme from Template, which are both in the Themes menu.