When I work I call in my spirit guides, healer guides, guardians, ancestors, ancients, ascended masters, angels, archangels, and saints. Depending on the work I am doing I may call in some or all of my helpers.
You may choose who you call in. If you work more with angels call them in. If you work with your spirit guides call them in. The shaman work I do calls for a wide variety of helpers who assist me. When you are in need to protection, help, assistance, healing, call them in. The more you work with them the more you feel comfortable calling them in.
In teaching healing I teach to learn who your guides are, who your helpers are and call them in. They will teach you, work through you, and protect you in every situation. When you make the commitment to do healing work (and mediumship is healing and healing is mediumship) your guides will happily step up to help you teach you and assist you in every way they can.
And I always always remember that the healing I do is my guides and their infinite wisdom. I am merely the conduit. I am always grateful and thank them each and every single time for letting me do this work and for my Light Workers working through me.