I watched a small part of a very good program the other day. It was something like "Secrets of the Psychics -- Revealed" and it was narrated by someone who sounded like Stacey Keech.

These are only a very few of the possible techniques used. Most I think would be more subtle.

My favorite was where a fake psychic gave the same scripted reading to 3 different people and all three thought it was dead on.