You can double-space all or part of a Word document.
To double-space the whole document, go to Design > Paragraph Spacing, and choose Double.
Tip: To double-space only part of the document, select the paragraphs you want to change, go to Home > Line and Paragraph Spacing, and choose 2.0.
Double-space the entire document
On the Home tab, in the Styles group, right-click Normal, and then click Modify.
Under Formatting, click the Double Space button, and then click OK.
Formatting for the entire document changes to double spacing.
Double-space the selected text
Select the text that you want to change.
On the Home tab, in the Paragraph group, click Line and Paragraph Spacing (Line Spacing in Word 2007) .