In order to truly partake in the Great Work, the goal for each one of us is to perfect ourselves the best we can through right thinking, actions and living. To take the higher path of the soul being that of our Lord into a more spiritual way of life while we live and operate in the material world.
We do this by taking reasonable control of all aspects of our lives to become one with our soul as we try to make ourselves, our loved ones and the world a better place than we found it.
Eliphas Levi says, The Great Work is, before all things, the creation of man by himself, that is to say, the full and entire conquest of his faculties and his future; it is especially the perfect emancipation of his will.
It is the Great Work of both spiritual and material worlds.
Manly P. Hall had written, Having become a citizen of two worlds, the individual must act accordingly. There can be no backsliding, because the individual must reach a state of certainty before this enlightenment is given that makes it utterly and completely impossible to backslide. He cannot get it and then fail and turn from it. If he turns from it, it means he never had it. If he fails, he fails himself. He cannot fail the infinite.
This is the science of being a true human, and the Great Work of the soul. The art of living in the light through our hearts, and the music of the soul that operates through love, reason, and empathy for all Gods creatures.
You are the conductor of this Great Work. Work that must be done on your own path down the road of evolution, or devolution. Therefor, you need to choose your thoughts, actions and life work wisely.