The easiest way to get NewFolder is to head on over to and fork or clone it as you see fit. You can also download the latest release as a zip file for your convenience. Drop the folder into your project, compile the SCSS, and go have fun!
I'm also working on NewFolder-based CMS themes. So far, I've made one for Typemill CMS, and you're looking at it right now. Read more about NewFolder for Typemill here.