How do you get a golem?
In the context of Pokémon, you get Golem by trading Graveler to another game and back.
Golems are ritually created statues meant to guard synagogues. To create a Golem you need three parts; the will, the body and the heart. The will is a scroll, written in sanscrit with the spell on it. The body is a statue of any description that must be carved prior to the ritual. The heart is your intentions and personal power. Golem require it to keep moving and have been known to drain amateurs to the point of death because they weren't smart enough to let their goal rest.
You don't. For the last couple of centuries, our spiritual level
has descended to the point that this has become impossible. Any
attempt would result in nothing.
You need to have a Graveler and trade it with a friend.
Here is a battle between Gengar and Golem. Gengar uses shadowball on Golem, then Golem uses rock throw. The shadowball explodes on the huge boulder. Golem uses rock throw again, but it does not work on shadowball. Shadowball effected Golem, but it does not kill it. Gengar uses thunder on Golem, but it does not effect golem because it is ground type. Golem uses stoneedge, causing it to die. Winner is golem.