Instructions for modification on sites created after March 2015 (V5).
This is done on the Styles section of your site, which is accessed from the editing dropdown in the top navigation bar (by default, the dropdown says Live Site).
Once you do that, you will be brought to the Styles overlay, which is where you will can build templates and set your new header.
To change the header image...
- Select the style you would like to change from the left column.
- Click Header.
- Click Change Header.
- Either choose an image from the pop-up menu that appears, or Find File to search your computer for an image you can Upload.
- Click Keep Change at the bottom left once you've selected the header you'd like.
- Click Activate All Changes.
- You're done!