Partially threaded coilovers raise and lower the car by raising or lowering the height of the spring on the coilovers. With partially threaded coilovers like the one shown, to raise the car, you will turn the collars up the shock body and to lower you will turn the collars down the shock body.
To adjust the coilovers, first, unlock collar B by taking your adjustment wrench and turn it clock-wise. Once loose, spin collar B by hand down the length of the coilover. You will then use the adjustment wrench to turn collar A clockwise to lower and counter-clockwise to raise the car. Once you have the perches adjusted to where you want it, spin collar B back up against collar A and use both provided adjustment wrenches to lock the collars against each other. To lock, turn collar B counter-clockwise and collar A clockwise.