How to Use Rulers in Microsoft Word
You can precisely adjust margins, text boxes and other elements in Microsoft Word 2013 using the Ruler command located in the Show group of the View ribbon. You can add the Ruler command to your Quick Access Toolbar to quickly hide or show your document's measurements in different views. You can adjust the units of measurement for your Ruler in the Display section of Advanced Word Options. Changes you make to your Ruler settings persist the next time you open Word.
Using the Ruler Command
Word displays a horizontal ruler at the top of your document in most views; however, a ruler is only available only in Print Layout view. Click on the "View" tab and then check the "Ruler" box in the Show group to display the ruler. Uncheck the "Ruler" box to hide the ruler. Right-click the "Ruler" box and then click "Add to Quick Access Toolbar" to easily toggle the Ruler command from any view in Word. Again, once changed, your Ruler settings persist the next time you open Word.
Configuring the Ruler in Advanced Display Options
If you need the ruler to measure elements in your document using a different unit of measure, you can change the measurements in Word's Advanced Display options. Click "File," and then "Options" to open Word Options. Click "Advanced" from the left sidebar and scroll to the Display section. Select your desired units of measurement from the box next to "Show Measurements in Units Of." For example, select "Centimeters" or "Points." Uncheck "Show Vertical Ruler in Print Layout View" if you want to disable the vertical ruler. Click "OK" to save your changes.