If you bank right you use a little right rudder, and if you bank left you use a little left rudder. The object being to keep the aircraft pointed in the direction of the turn. Using opposite rudder is called banking without a turn. Thus if your flying eat, and you apply a little left aileron, and a lot of right rudder the plane will keep going east but it will slide sideways.
You only use a little rudder for a coordinated turn. Really it's only for scale like turning anyway. Also coordinated turns are smoother, and bleed less speed.