Pray anytime of the year - the most popular time is nine days prior to the Feast of the Epiphany (with the 9th day being the feast day) 

Day 1

O holy Magi, you were living in continual expectation of the rising of the Star of Jacob, which would announce the birth of the true Son of Justice, obtain for us an increase of faith and charity, and the grace to live in continual hope of beholding one day the light of Heavenly glory and eternal joy.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.

Day 2

O holy Magi, who at the first appearance of the wondrous star left your native country to go and seek the newborn King of the Jews, obtain for us the grace of corresponding with alacrity to every Divine inspiration.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.

Day 3

O holy Magi, who regarded neither the severity of the season, nor the inconveniences of the journey, that you might find the new-born Messiah; obtain for us the grace not to allow ourselves to be discouraged by any of the difficulties which may meet us in the way of salvation.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.

Day 4

O holy Magi, who when deserted by the star in the city of Jerusalem, sought humbly, and without human respect, from the rulers of the Church, the place where you might discover the object of your journey, obtain for us the grace to have recourse, in faith and humility, in all our doubts and perplexities to the counsel of our superiors, who hold the place of God on Earth.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.

Day 5

O holy Magi, who were gladdened by the reappearance of the star which led you to Bethlehem, obtain for us from God the grace that, remaining always faithful to Him in afflictions, we may be consoled in time by His glory.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.

Day 6

O holy Magi, who, entering full of faith into the stable of Bethlehem, prostrated yourselves on the Earth, to adore the new-born King of the Jews, though He was surrounded only by signs of poverty and weakness, obtain from the Lord for us a lively faith in the real presence of Jesus in the Blessed Sacrament, the True Spirit of poverty, and a Christlike charity for the poor and suffering.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.

Day 7

O holy Magi, who offered to Jesus Christ gold, incense, and myrrh, thereby recognizing Him to be at once King, God, and Man, obtain from the Lord for us the grace never to present ourselves before Him with empty hands, but that we may continually offer to Him the gold of charity, the incense of prayer, and the myrrh of penance and mortification.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.

Day 8

O holy Magi, who when warned by an angel not to return to Herod, traveled back to your country by another road, obtain for us from the Lord the grace that, after having found Him by true repentance, we may avoid all danger of losing Him again.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.

Day 9

O holy Magi, who were the first among the Gentiles called to the knowledge of Jesus Christ, and who persevered in the faith until your deaths, obtain for us from the Lord the grace of living always in conformity to the baptismal promises and especially in accordance with our religious vows leading ever a life of faith, that like you we may attain to beatific vision of that God Who now is the Object of our faith.

Glory Be to the Father, and to the Son, and to the Holy Spirit.  As it was in the beginning, is now and ever shall be; World without end.  Amen.