If you write a lot of legal documents or other types of documents in which you need to reference specific sections, adding line numbers can be useful. We will show you how to add unobtrusive line numbers in the left margin of a Word document.
Open your Word document and click the Page Layout tab on the ribbon.
In the Page Setup section of the Page Layout tab, click Line Numbers and select Line Numbering Options from the drop-down menu.
On the Page Setup dialog box, click the Layout tab. Then, click Line Numbers.
The Line Numbers dialog box displays. Select the Add line numbering check box so there is a check mark in the box. Specify the number to Start at, the increment to Count by, the distance From text, and whether to number continuously or restart at each page or section. Click OK.
Click OK on the Page Setup dialog box to close it.
You can easily change the options or turn off the numbering when it’s not needed.