A fellow investigator of mine actually attended a
Womens Institute meeting and convinced them he was psychic by standing up and giving readings. "I have a someone hear who's name begins with J...Jack, John, Jonathan...yes thats it Joshua" etc. He admitted his duplicity at the end and used it as an example of how it can be faked. He was amazed though that after his admission some of the audience came up to him saying he was so accurate he must have the gift.
I think that reading body language, checking for rings, seeing if they have rough or smooth hands, manicures, clothing, expensive hair do's etc all can give you details about someone that you can use to fake a reading.
As I have said, I believe there are genuine psychics but we must be prepared to accept there are many fakes.