$ sudo npm install gulp-cssmin
$ sudo npm install -g gulp-cssmin

If want to update the gulp-cssmin package execute the command as below,

$ sudo npm update gulp-cssmin

Update package globally,

$ npm install -g gulp-cssmin

Git clone:

$ sudo  git clone https://github.com/rektide/gulp-cssmin.git

$ sudo  npm install -g ./gulp-cssmin

gulp-cssmin@0.2.0 /usr/lib/node_modules/gulp-cssmin

How to remove gulp-cssmin package :

You can uninstall or remove this package from your node_modules run the command as below,

$ sudo npm uninstall gulp-cssmin

Basic Information of gulp-cssmin NPM Package: