It is a 2 step process. Install Node.Js, followed by Installing the Node-RED application.
Node-RED is a visual flow editor where you can connect devices and set up flows based on inputs from devices like Microcontrollers and tell it how to go about based in input from devices.
http://nodered.org/docs/getting-started/installation.html

Steo 2:

Finally Launch Node-RED:



Launches the application.













































