Every day, pray the Serran Prayer for Vocations
Of course, we need to pray for all vocations every day, including those to the religious life, and that everyone find out and follow their calling to whatever station in life God wants for them.
Here is the Serra Club's prayer for vocations to the priesthood:
O God, Who will not the death of a sinner but rather that he be converted and live, grant, we beseech Thee, through the intercession of the Blessed Mary, ever Virgin, St. Joseph, her spouse, Blessed Junipero Serra and all the saints, an increase of laborers for Thy Church, fellow laborers with Christ, to spend and consume themselves for souls. Through the same Jesus Christ, Thy Son, Who lives and reigns with Thee in the unity of the Holy Spirit, God forever and ever. Amen.