You can add edit Headers and Footers in the Settings menu.
- Access the Settings menu with the keyboard short cut
⌘ ,or by clicking the Settings ‘gear icon’ and then clicking ‘All settings’
- Select ‘Headers and Footers’ in the menu on the left.
- Click on the text box you wish to edit in the Header or Footer.
- Type your text or click on the macro snippet you wish to occupy that box (which will automatically generate the denoted text).