The instruction manual for the Tein Flex suggest turning all the way to the right to seat the damper fully. Then adjust back until you click 16 clicks. From that point you turn back 8 to get a 50% dampening as a baseline. Then go up or down for your liking.
Ride height is adjusted after you preload the spring. The instruction manual has specific heights for top of damper to bottom of spring, top of damper to bolt hole at bottom of damper, etc. Get all these adjustments right and you will be happy. You can then decide of you wish to lower it a little more. Too much and your lock out clamps/washers will rub on the control arm. Your tire will also rub on the fender and potentially bend it.
You can obtain the instruction manual from Tein off their website.