Jim,
It is pretty simple. Of course I have tested mine and found the setting that works best for me. Now every time I get ready to roll all I have to do is hold the slide over (manually apply brakes) and I get a power read out on the LED. I have found that 7. 2-7. 4 works best for me, so while holding the slide I adjust the controler to read 7. 2. This setting may not be best for you depending on trailer size etc, but you could start out a little lower ( say in the 6s) untill you have tried the brakes a few times, then adjust accordingly. Once you find the right setting it is so easy to check and set the controler and you will get consistant breaking every time. My favorite feature is the boost settings, Ireally like level 2. I can hardly tell there is any delay.
Fireman