1. Click anywhere in your document
2. Click on the ‘Page Layout’ tab
3. Click the ‘Margins’ button – the margins gallery will appear as a drop-down on your screen with a list of pre-defined margins.
Click on any one of the pre-defined margins
4. If the margins you need are not found in the pre-defined margins – scroll right to the bottom of the margin gallery and click on ‘Custom margins’ – the page dialog box will appear.
See the Diagram below:
6. Here you can change the ‘Top’, ‘Bottom’, ‘Left’ and ‘Right’ margins to the size you want. (See Diagram below)
When you are done, click the ‘OK’ button.
Word will apply the changes to your document.