Full installation of Leo requires that you:

1. Install Python
2. Install the Leo files

To install Python, follow the directions on this page.

To install Leo, go to this page and download the most recent zip file under the heading "Leo2.py". Download the zip file to your desktop or other location, and then unzip it to the folder of your choice.

To run Leo, double-click on the file leo.py that you have just unzipped.