After getting and installing nodeJS and Node-red, guide on how to do so is here: (http://developer.opto22.com/nodered/general/getting-started/node-red-install-red/)
After that you will need to find where your flow file is stored, on windows it is generally something like \Users\YourUser.node-red
The file you are looking for will be called "flow_YourComputerName" if it does not excist then it means that you need to start node red with the "node-red" command then open the console in a browser using the address that is provided in the terminal, then put anything in the flow and deploy it.
Open this file in a text editor and replace all the code with the one in the file provided in this repository, then save it.
You can then play around with the code in the console adding whatever messages you want in the randomised function. To make it work you will need to add your own twitter credentials as I don't want you using mine!