Here is a short video showing a very simple way to help release the tight tissues of the piriformis and glute.  The ball used in the video is very hard and is not suggested for people who have never performed any self-massage prior.  I would recommend using a mini soccer or basketball were the amount of inflation and therefore pressure can be controlled.  Also note that breathing is a very important component to success when using self-massage.  You must be able to breath relaxed or the tissues will not respond in the fashion we would like.  You may also find that the area is just to painful to put any pressure on…start by working with the tissues that are not painful and work toward the more painful areas…again remembering to breath!!!

Watch here