It’s the one you pray right now.
We moderns have a tendency to be very method-oriented, wondering how we can “life-hack” our spiritual lives. But the fact of the matter is that prayer is contact with God, and God is love. Reducing love to mere method and “button-pushery” is not love at all.
Today, jump in to the adventure of prayer. Because the best prayer you can pray is the one that you pray right now.