Word – How to reduce the size of the header / footer in microsoft word

You can do this using the Restrict Editing button on the Developer tab. The Developer tab isn't visible by default--if you don't see it, the option to display it is under File | Options | Customize Ribbon (Microsoft Support article with steps).

1. Format your headers and footers the way you want them.
2. Select Restrict Editing on the Developer tab.
3. Under 2. Editing restrictions, select No changes (Read Only).
4. Select the body of the document. Under Exceptions, check Everyone. (If you have formatting marks displayed, you'll see a gray I-bar appear in the document.)
5. Under 3. Start enforcement, select Yes, Start enforcing protection. Enter a password if you want one, or leave it blank for no password. (Not selecting a password means that employees can remove the protections if they're that bound and determined to mess with your formatting, and if they know how.)