Just like any other node.js project I just created a new folder, did an npm init, and installed the latest version of acorn. As of this writing the latest version of acorn is 5.3.0.
I then also made a demos folder, and made my first demo called basic.js. It is a usual practice of mine to start out with a demo like that when trying out a project of any kind.
When calling this script from the command line I end up getting this: