Usually I send out 'flash' prayers...prayers so quick you could miss them if you weren't listening closely. Often times they are one sentence prayers. Then, later I feel I've really let down the person I was praying for....not allowing much time to concentrate on them.
The method presented in the book Praying in Color by Sybil MacBeth causes me to slow down and really think about the person/situation and look at all the different areas that need to be presented to God.
In a nutshell, I write the name of the person or situation and encircle it with a shape, any shape. Then I add more shapes and lines to the first shape. In my style, I usually create random criss-cross lines and curlie-Q's around the name which creates various shapes. I then decorate those shapes with gel pens of various colors, metallic, sparkle pens, etc. As I decorate I think (spend time) with the person, and as areas of need come to my mind, I offer them to God. When I'm finished, I feel like I've really interceded for that person and I am satisfied.
Here are some examples: