What you'll do: decide whether a section shows up in the e-book, the print PDF, or both — and, for print, which page it begins on.
Each section on the Matter step has two small dropdowns for this.

Include in: e-book, print, or both
The Include in dropdown lets you choose:
- All — appears in both the EPUB and the print PDF (the usual choice).
- E-Book — only in the EPUB.
- Print — only in the print PDF.
- None — kept but not output anywhere.
This is handy when a page only makes sense in one edition — for example a "Scan this QR code" page that belongs in the print book but not the e-book.
Begin on: which page (print only)
The Begin on dropdown controls where the section starts in the printed book:
- Any page — starts wherever the previous content ends.
- Right page — always starts on a right-hand page (a recto), the traditional place for a new section. Bookbndr inserts a blank page if needed.
- Left page — always starts on a left-hand page (a verso).
This setting has no effect in the e-book, where pages aren't fixed.