Francis DeSales, 1576-1622, was a Roman Catholic bishop of Geneva. He was an accomplished preacher in his day. His preaching often lead people to seek his spiritual counsel. He is known also for his writings on the topic of spiritual direction and spiritual formation. The following excerpt is from his book, Introduction to the Devout Life.

The first consists in a lively and attentive apprehension of God's absolute presence. That is, that God is in all things and in every place. There is not a place in the world in which he is not most truly present. Just as birds, wherever they fly, always meet with the air, so we, wherever we go, or wherever we are, always find God present. 

Everyone knows this truth, but everyone does not fully reflect upon it. Blind men, who do not see a prince who is present among them, behave with respect when they are told of his presence. However, because they do not see him, they easily forget that he is present, and having forgotten it, they still more easily lose their respect for him. Alas, Philothea, we do not see God, who is present with us. Although faith assures us of his presence, yet because we do not behold him with our eyes, we too often forget him and behave as though he were very far away from us. Although we all know that he is present in all things, because we do not reflect upon it, we act as if we did not know it. That is why before prayer we must always excite in our souls a lively thought and apprehension of the presence of God.... 

The second means to place yourself in his sacred presence is to reflect that God is not only in the place in which you are, but that he is, in a most particular manner, in your heart and in the very center of your spirit. This he enlivens and animates by his divine presence, being there as the heart of your heart and as the spirit of your spirit....  And as St. Paul says that it is in God “we live, and move, and are.” Therefore, in consideration of this truth, excite in your heart a profound reverence towards God, who is there so intimately present. 

A third means is to consider our Savior in his humanity looking down from heaven on all mankind, but especially on Christians, who are his children, and more particularly on such as are at prayer, whose actions and behavior he observes. This is by no means a mere imagination, but a very truth…

A fourth method consists in making use of the imagination, by representing to ourselves our Savior in his sacred humanity, as if he were near us, as we sometimes imagine a friend to be present, saying “I imagine that I see him who has done this or that,” or “It seems to me that I see him,” or something similar…

Hence, you will employ one of these four means of placing yourself in the presence of God before prayer. Do not use them all at once, but one at a time, and that briefly and simply.
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