Sure this is easier said then done but it is a daily practice. On the days or occasions that I am unhappy, angry or not at peace I remind myself of the Serenity Prayer – “God grant me the serenity to accept the things that I can not change; courage to change the things that I can; and the wisdom to know the difference”. You will hear me mention this prayer a lot, I carry a copy of it around with me as it is  on the back of my business card. Just remember that ultimately you are in control of how you feel or react to any given situation.