I believe I give better readings if I do not know any details about the spirit you are wanting contact with. That way should I get specific content it better verifies the reading for you. I do the same thing for my Psychic readings I feel I do better if I don't know the question.
To obtain additional information or energy from the spirit, it does help to bring a personal item of the loved one. This can be anything they kept on them and has their energy imprinted on it. Some of the best items to bring are hand writing of the person.