Steps are below:
In package.json add:
"bin":{
"script1": "bin/script1.js"
}
Create a bin folder in the project directory and add file runScript1.js with the code:
#! /usr/bin/env node
var shell = require("shelljs");
shell.exec("node step1script.js");
Run npm install shelljs in terminal
Run npm link in terminal
From terminal you can now run script1 which will run node script1.js
Reference: http://blog.npmjs.org/post/118810260230/building-a-simple-command-line-tool-with-npm