more detailed instructions here: http://kodi.wiki/view/HOW-TO:Install_an_Add-on_from_a_zip_file
- download the add-on as a ZIP file (click on the green "Clone or download button" then click on the "Download ZIP" link)
- open Kodi
- go to
Add-ons -> click on the opened box in top left corner -> Install from zip file -> navigate to the downloaded zip file - select the zip file.