Make sure gitbook cli is installed

npm install gitbook-cli -g

Create the directories and files for a book from its SUMMARY.md file (if existing) using

$ gitbook init

You can serve a repository as a book using:

$ gitbook serve

Or simply build the static website using:

$ gitbook build

You need to have ebook-convert installed

gitbook pdf ./myrepo ./mybook.pdf
gitbook epub ./myrepo ./mybook.epub
gitbook mobi ./myrepo ./mybook.mobi
gitbook build ./myrepo --format=json