Our attitude is affected by many things, but most importantly it is something that we have the power to shape.
While reactions are somewhat controlled by temperament, you can consciously examine and shape your thinking about situations that you're in. The ability to examine your attitude - and change it when necessary - is the creative role that you can play. The story you tell yourself minute by minute is a powerful creative force in your life.
Listen to what you are telling yourself throughout the day. When faced with a negative thought, turn it around to make it into a positive thought.