Physical mediumship is different then mental mediums as physical mediums display much more determination and practice in order to reach this level of mediumship.
Mediums enter into a circle and can summon a spirit and talk through them, or hear them. Physical mediums can summon the spirits, however, everyone else present can also see and feel the spirits as well. This differs from regular mediums as they remain the only ones who can see the spirits during a session.
“Physical medium-ship is the process whereby someone, in Spirit, usually known as a spirit operator (as compared to a spirit communicator), works or operates through the mental AND physical energies of the medium and causes something physical to happen on the Earth plane. Physical medium-ship is objective in nature; that is, when the phenomena occur, everyone is able to see and/or hear them.” – fst.org
It takes a lot of practice and years dedicated to developing their skills in order for mediums too become physical mediums.
Physical mediums do not practice and develop their skills for themselves, however they do this so that the people who summon them for mediumship will be able to feel and see the spirits that they want to summon.