Cho Ku Rei, which is considered one of the first symbols used in Usui Reiki essentially means “Placing all the powers of the universe here”. The Reiki power symbol basically works as a “switch” that helps to instantly increase Reiki practitioner’s ability to channel the energies. The main purpose of using it is to enhance the power of Reiki and draw the energy around and concentrate it on the required purpose.
Using this symbol mentally is useful in clearing all the stagnated energies during a Reiki session. Similarly, drawing it on the walls of a room clears the negative energy in the room, and drawing it in the atmosphere around a physical space aids in cleansing the area. Drawing can be physical, such as with paint or a pen, or symbolic with the hand in the air.