Setting Margins in Word

Hi girls, I have decided to make my own save the date cards rather than try and get them from the U.S. does anyone know how to set margins in Word so I can print the pictures on the cards. They would be the C6 size. I'm sure there are instructions somewhere on how to work it out but I don't know where to look. Thanks,

Go to page setup in the file menu. There should be an option for page size there.