These video demos might help you learn to use the kit.
http://pool9.net/K2006-vid/
http://pool9.net/tk-interfere/

If you are getting a reading of 5 on your test kit, then it could be 5 or any number over 5 since that is the highest number on the scale. Check this link. It shows colors of higher readings than your OTO kit can read. http://pool9.net/oto-chart/

Based on that chart, what would you say that your chlorine reading is?