You put it in with a ~2 foot piece of pipe with an end cap and a handle
or two on it. You can rent 'em from rental places or sometimes the local
home Honey-Do Emporium. Wear the thickest, foamiest gloves you have so
you'll be able to feel your hand when done pounding. How far in depends
on your year-around soil moisture conditions....yup, all the way in,
unless you hit an aquafer! :) Leave about 6" out for connecting your
wire and then spray paint it to keep the oxidation down. On the same day,
once a year,when you change the batteries in your smoke detectors, go out
and check/tighten it.
I put a BLUNT point on mine to help go arount the rocks and hardpan. A
sharp point makes it wander too much.
The latest one was for 240VAC hot tub gounding. It has GOTTA work!