Will be the same as any other coilover, you can wind the spring seat down or you can adjust the base. I'd lower the spring seat. There should be two rings below the spring (they will be right up against each other), the top one adjusts for height and the bottom one locks the top one into place. Undo the bottom one the set your height with the top one, then tighten the bottom ring against the top ring. Easier if you just youtube it.
I like the MCA method:
Basically you take the spring out, install the shock and put the wheel on, then jack the wheel up. You then make adjustments to the base height (bottom screw thing which attaches to the knuckle) so that when the shock absorber is bottomed out the wheel is not making contact with any part of the car. Then you put the spring back in and change the spring seat height to get the desired ride height. You only have to do this on one side of the car as you just copy those measurements to the other.