In art the ka was portrayed in several ways: a person identical to the person whom it was associated with, as a shadowy figure, as a person with two upraised arms on his head. The hieroglyph for the ka was the shoulders and arms with the arms bent upwards at the elbow, similar to the "touchdown" gesture in American football.
The "ka" is a very complex part of the symbolism in ancient Egyptian mythology and represents several things: the ka is a symbol of the reception of the life powers from each man from the gods, it is the source of these powers, and it is the spiritual double that resides with every man.
The ka as a spiritual double was born with every man and lived on after he died as long as it had a place to live. The ka lived within the body of the individual and therefore needed that body after death. This is why the Egyptians mummified their dead. If the body decomposed, their spiritual double would die and the deceased would lose their chance for eternal life. An Egyptian euphemism for death was "going to one's ka". After death the ka became supreme. Kings thus claimed to have multiple kas. Rameses II announced that he had over 20.
The ka was more than that though. When the ka acted, all was well, both spiritually and materially. Sin was called "an abomination of the ka". The ka could also be seen as the conscience or guide of each individual, urging kindness, quietude, honor and compassion. In images and statues of the ka, they are depicted as their owner in an idealized state of youth, vigor and beauty. The ka is the origin and giver of all the Egyptians saw as desirable, especially eternal life.
Kas resided in the gods as well. Egyptians often placated the kas of the deities in order to receive favors. The divine kas also served as guardians. Osiris was often called the ka of the pyramids.
The god Khnemu who was said to create each man out of clay on his potter's wheel also molded the ka at the same time. (Egyptian Myths)