Select the text you want to change.
On the Formatting toolbar (toolbar: A bar with buttons and options that you use to carry out commands.
To display a toolbar, click Customize on the Tools menu, and then click the Toolbars tab.), point to Line Spacing , and then do one of the following:
To apply a new setting, click the arrow, and then select the number that you want.
To apply the most recently used setting, click the button.
To set more precise measurements, click the arrow, click More, and then select the options you want under Line Spacing