Uploading Your Ebook Cover in Pressbooks
To upload your book cover file in Pressbooks:
- Make sure your book cover is at least 666x1000px (recommended 2500x3750px)
- Go to Left Menu -- Book Info.
- Scroll down to "Cover Image." Click Choose File and locate your book cover file on your computer.
- Click Choose to upload that file into the Pressbooks system.
Pressbooks will then include your ebook cover in your MOBI and EPUB file exports.