My Basic template for the _output file of a bookdown project. Additional files needed are within this gist in future (2022)

_output_template.yml

bookdown::gitbook:
  css: style.css
  config:
    toc:
      before: |
        <li><a href="./">Book title.</a></li>
      after: |
        <li><a href="https://github.com/username/repo" target="blank">Published with bookdown</a></li>
    edit: https://github.com/username/repo/docs/edit/master/%s
    download: ["pdf", "epub", "mobi", "docx"]
    link-citations: yes
bookdown::pdf_book:
  #includes:
    #in_header: preamble.tex
  latex_engine: xelatex
  citation_package: natbib
bookdown::epub_book: default
bookdown::word_document2:
  #reference_docx: ms.docx
  fig_caption: yes
  toc: yes
bookdown::html_document2:
  theme: yeti
  fig_caption: yes
  toc: yes
  toc_float: true
  code_folding: hide
  df_print: paged
  number_sections: false