Where to Rest Your Awareness in Centering Prayer

A reader of this blog recently wrote this question to me:

I’ve read and listened to Fr. Thomas Keating quite a bit but am still a little confused regarding where my mind is supposed to be during my Centering Prayer practice. I understand that we are to use the sacred word as a symbol of intention to accept the presence and action of God, however, I get tripped up over where my awareness is supposed to rest. Am I supposed to sit with open awareness AND with the sense that God is present or am I s...