Controlling a Stepper Motor with Arduino

For a four-wire stepper motor, you need two full-bridge power drivers, one for each winding.

Also, due to the inductance of the windings, for anything other than extremely low speeds, they must be driven from a high voltage supply using constant current drivers.

The simplest approach is to use one of the readily available stepper motor driver modules such as these:

There are arduino libraries for controlling steppers using modules such as those.

The motor supply to the driver module should be somewhere in the 12V - 24V range.

The modules also include microstepping, so the motor can be positioned to an accuracy of eg. 1/16 it's full step angle.