Listen and take notes

When you interview a client, make sure to take notes. Keep all your distractions away (resist the urge to check that email) and make your client feel as important as a movie star giving an interview, or a political candidate holding a press conference. Listen to them. Let them speak their mind and then ask some insightful questions. Sometimes their biases or a strong opinion comes out. Do not react but listen through this, take notes.

Of course it would be a sin if you are taking notes on a sheet of papers of the back of an envelope.  Also, avoid using flashy folders. My wife once gave me one and the Partner commented on it and it distracted me from the entire interview session.