Click on the More Information button above to see the details.
Download and unzip the script - the file name will be "Low Battery Notification.py". You can put this script wherever you want, but I recommend putting it here:
/Library/Application Support/Perceptive Automation/Indigo 7/Scripts/
Note that's the Library folder at the top level of your hard drive, not the one in your home folder.
There are several ways you can run this script: once a day is probably the easiest. You can get clever however and run it every hour. Add some current time conditions to the schedule and it can notify you once an hour between, say, 6pm and 10pm. Lots of options.