Go to the Responsive Software website.
Click on the button that says "Click Here To Download".
When it asks do you wish to Run or Save or Save As choose "Save As".
Then save the program to your desktop (or create a folder for it and put a shortcut on the desktop.)
When you run it the first time another file LedgerLite.LLD will get created automatically.
This file contains a creation date stamp that allows it to be used during the 30 day free trial period.
After that you need to enter the company name and registration code to continue using it indefinitely.