Enter the stillness of interior prayer--in a crowded room or in the silence of your prayer place. Be present here and now. Present to each breath, the name and mercy of Jesus attached to each inhalation, each exhalation. To each thought that passes through the mind; present and poised so that you follow your breath and prayer rather than each maverick thought.
This practice may be new for you. A steady stream of thoughts pass through your mind. They urge you to follow wherever they, undisciplined and self-centered, want to take you. They don't care that you want to go somewhere else, do something else. They don't care that you're trying to pray and meet with God.
You might never before have realized that you have a choice when presented with this stream of thoughts. You have a choice to follow them or not. In fact, it is imperative that you choose, for choosing means that you are living from the center, your true heart, where Christ reigns within you.