Is there a way to set a default header in Microsoft Word?

I use Microsoft Word on my Mac Book for school. Since I am a freshman in high school, the concept of MLA format has been introduced to me. I am required to write all of my essays in this format with no exceptions. MLA format calls for a header of the page number and my last name in the top right corner. Is there any way to set this particular header as the default for a new doent so I don't have to reset it each time and get docked points when I occasionally forget? Thanks!