To lower a car you can use lowering blocks and install the lowering blocks on top of the cars axle.
The lowering blocks can be purchased online.
You can also lower a car by removing your car's 4 coil springs from the front or back suspension and take them to an auto shop and have them shortened or even cut them yourself with a grinder.
Other ways to lower a car are to use lowering springs, air suspension and coilovers.
Lowering springs replace the stock springs with shorter ones and lowers the car.
Coilovers are adjustable spring and shock units which can be raised or even lowered.
And air suspension uses airbags and a management system to change the cars ride height on the fly when you want to lower or raise the car.
Altering the springs of a cars suspension is a common practice amongst tuners for lowering a vehicle.
One way of lowering your car's suspension is to adjust or replace the springs with shorter ones.
Doing this is a cheaper and more economical way of lowering your car's suspension.
Lowriding a car is legal so there's no law against having a car lowered if you want to lower the car.