by Reb Aharon Rubin, from Eye to the Infinite, shared with permission.
& Consciously repeating words and phrases
We said earlier that repetition acts like a mantra on the mind. In the time of the Mishna, saints would repeat certain words, to ascend the spiritual worlds. The fact that we repeat G-d’s Name (Adon-oy (lit. my Master)) so often, will in time, if concentrated upon each time, produce a deep-seated feeling of standing before the Master of the world.
The poetic hymn, אדון עולם Adon Olom “Master of the Universe”, was placed at the beginning of the morning prayers to help create a mindful awareness of G-d. Its opening words make for a perfect preparatory visualisation, paving the way to meaningful communication.
Intone the words, “Adon Olom”, “Master of the universe”, slowly and softly. See yourself before G-d. G-d is looking at you. Contemplate how He oversees everything. He ‘fills’ everything: the Universe with all its galaxies and zillions of stars, the Milky Way, our Solar system, planet Earth with its intricacies and minutiae and the spiritual worlds, infinitely greater than all physical reality.
Meditate on how He creates and sustains everything with His Thought and Word; how, therefore, all is as nothing before Him, the Infinite One, Master of the Universe, Who fills all those worlds and before Whose Presence you now stand.
The words, אדון עולם Adon Olom, have the same gematriah as אין סוף Ein Sof (The Infinite), which are also the gematriah of אור Ohr, ‘Light’. Think about that. The omniscient Master of the Universe is Ein Sof, Without End; His infinite transcendental light is equally omnipresent, beyond constraints of time or space.
This meditation need not take long. Spend a couple of moments awakening your natural awe and love for G-d. These feelings should be remembered each time you mention G-d’s Name, ADoN-oY. Should you feel your concentration faltering while praying, recalling these words will reawaken your love and awe of G-d.
 Probably composed by Rabbi Shlomo Ibn Gabirol (1021-1058), it is customarily said at the beginning of Shach'rith. See Seder HaYom. Mateh Moshe, para. §31, in the name of Rabbi Yehudoh HaChosid quoting the great Rabbi Sheriroh Gaon and his son, the great Rabbi Hai Gaon, that whosoever says [and contemplates] Adon Olom before prayer is promised that his prayers will be accepted.
 Daniel 4:32, Zohar I, 11b, Chagigoh 13a. See also L.A. Tanya, Iggereth HaQodesh.
 See though Shulchon Oruch, Orach Chaim §5.