It's good for a psychiatrist to think of a patient in a holistic way, and to ask the patient about diet, exercise, sleep, relationships, support systems, and different stressors in their life in order to make an informed assessment and a proper evaluation.
It is also important for the psychiatrist to possess some degree of humility when speaking to the patient, even admitting to not knowing something if that is the case, and telling the patient that he will look into the matter. This shows a partnership and a collaboration with the patient, which will produce more success in the end.
It also goes without saying that a psychiatrist needs to be able to really listen to his/her client, and convey authentic concern, always being respectful of the patient's feelings.