Sardi has an icon set named Sardi Mono Numix which combines monochrome applications with yellow folders. Like so.
BUT you can as easily mix them with Sardi icons instead of the Sardi Mono icons. That is the topic at hand in the tutorial.
OR
Just download all the extra made Sardi icon themes from google drive. You will need the Sardi icon themes from Sourceforge too since they depend on each other.
Extract the compressed files and put them in the hidden folder .icons
Content of the tutorial
- Copy/paste a suitable candidate
- rename the folder
- rename the name inside the index.theme
- change the inherits line