It's an error to try to achieve a particular emotion by concentrating on it, because it will only lead to "indicated" acting. It's also an error to consider "cognition" narrowly. We receive a stimulus from the environment or from a thought process, which then produces an emotion. Never think of the "feeling," or, as some students have attempted: To get into the "mood."
Watch "How I Became the Bomb - Ulay, Oh...posted below.