Seven Fields of Human Aura
Corresponding with seven chakras, there are seven layers of human aura, namely, divine body, spiritual body, casual body, mental body, emotional astral body, etheric body and physical auric body. These layers are also called energy fields of human aura. Each field has its own color, yet there is an overall color of the aura.
Protecting the AuraOne might be exposed to negative energies anywhere but the chances of exposure become far too great when you move around in public places. You might come across any type of person or object that could have the capability (stronger aura than yours) to affect your aura and pass negative energy. Since it is nearly impossible to identify such energies instantaneously in advance and avoid them, it would be better to keep oneself protected. There is a way to keep the aura protected against negative energies. It hardly takes few minutes to do so. One should make it a habit to protect the aura before leaving the house in the morning and keep it protected till return. However, please remember that such protection is not against physical phenomenon like hitting your knee against a table etc. The protection is against undesirable energies not against the physical objects.
Your Reiki teacher would teach you the technique. Remind him in case he forgets. I teach this to my students during their Reiki training with me.