The Moon's Map is accesed via the "map" option in the menu. It consists of 77 tiles that are unlocked as each of the 77 bewitchments are solved. The tiles must be pieced together in their correct places using clues from the story. Once the map is assembled, a new series of puzzles is unlocked, which are accessible only from the map screen.
The hint for the map screen states "Heed the Knowledge of the Four to Assemble the Moon's Map".