Probably best to look up instructions in their Wiki so you can do it via your system's package manager: https://github.com/joyent/node/wiki/Installing-Node.js-via-package-manager
Best stick to the installer route here: Get the latest from http://nodejs.org/
sudo gem install sass
sudo gem install compass
sudo apt-get install ruby
sudo apt-get install rubygems
sudo gem install sass
sudo gem install compass
Get Ruby from http://rubyinstaller.org/
gem install sass
gem install compass
I like to keep my projects self-contained as much as possible so I install Grunt on a per-project bases.
First change to your project directory in your CLI of choice.
sudo npm install grunt-cli --save-dev
npm install grunt-cli --save-dev
The above will install grunt and grunt-cli but by default this will not work because grunt-cli needs to be in your PATH.
Add the relative path to your path. This will work but only if you're in your site's root directory.
Add export PATH="./node_modules/.bin:$PATH" to ~/.profile
Add .\node_modules\.bin; to the start of the PATH environment variable (This is done through Advanced System Settings)
TODO
Install grunt-cli globally. This has the potential to introduce cross-project version problems as all projects will use the global version of grunt-cli not the version that they have listed in their dependencies.
sudo npm install -g grunt-cli
npm install -g grunt-cli
Use the local version by calling it directly:
TODO
.\node_modules\.bin\grunt