In the simplest use-case, just navigate to the directory your file is in, and type:
pyinstaller myfile.py
Pyinstaller analyzes the file and creates:
myfile.py
myfile.py
myfile.py
The bundled app can be found in the dist folder
Options
There are several options that can be used with pyinstaller. A full list of the options can be found here.
Once bundled your app can be run by opening 'dist\myfile\myfile.exe'.