If the appliance has a 3-prong plug on it, and if the wiring in the house was
done legally by a licensed electrician, then the appliance is already grounded,
through the third prong, as soon as you plug it into a 3-prong outlet (socket).
If the plug on the end of the power cord only has 2 prongs, or the third prong is
cut off, or it's plugged into a 2-prong outlet somehow, then you should ground it.
This is probably the simplest way:
-- Connect a piece of wire from any screw on the metal case of the appliance,
to the screw in the middle of the cover that holds the cover onto the pair of
AC outlets.
-- Don't toast bread with the appliance when you're in the bathtub.
