I visualize the shape of prayer like an enormous triangle. Looking at the triangle, I imagine the top—the peak—is God. The left bottom angle is me, the one speaking the prayer. The third angle, the extreme right corner, is the man or woman for whom a prayer is being said.
Next, I visualize two lines going out from myself, the one offering prayer, from that left-handed angle corner. One line goes up from me to God. The other extends, on the horizontal level from my heart, to the one in need. I look up to God, and also over to the one for whom the prayer is being spoken.
Then I see two lines flowing down from God. One goes to the person being prayed for, the other comes back down to me, the pray-er. The line that goes to the one in need is God's energy and love streaming with strength, love, healing and courage, as needed. The line from God to me is God's love and energy flowing back to me, the one in prayer. It does not stay with me, however. It flows from there, through me, out toward the needy one, for whom supplication and intercession is being offered.
The often overlooked part of this picture is God's healing love flowing through the one doing the praying. The help doesn't exclusively come down directly from God to the hurting person. That incomparable source is complemented by the love and energy of God sent from me, the one personally praying.
Suggestion for a mental image:
When praying for someone, if I am not in their presence, I find it helpful to conjure up a mental picture of him, or her. I see them in my mind. I think of them in such a way that I can visualize them rather clearly. This, then, multiplies the loving energy of God flowing toward them. It streams directly from God, and also through me.