I read somewhere that a photographer should be able to take a picture in his mind, even when he/she doesn't have a camera in hand. I think this is a good start for training, and in exploring our imaginations. Of course, if you have a camera in hand and you are right in front of a decisive moment, you should never miss that moment.
Today I was having brunch at my college canteen. I chose a table in the corner, as I ate my buns, scrambled eggs and sipping ice tea, the sun was shining down on my table. I also felt the warm heat of the sun on my face. Simutaneously, the reflected light from my plate hit my eyes. The sunlight wasn't harsh, I was sitting alone, I cannot see myself as there was no mirrior. But my senses told me that it was a perfect lighting for a photograph. So in my mind's eye, I picture myself from the opposite end - eating and sitting alone on a table, sunlight hitting some parts of my face and my hair, and the reflected light from my plate highlighting my eyes. That would have made a pretty picture, whether it was me or any other person.
And just opposite to me, there was a girl sitting alone as I was, sitting under the shade of a tree. She was also eating her lunch. There was a streak of sunlight shining through the branches of the tree. It highlighted her hair. And below the table, one of the campus dogs was deep in his sleep. I captured that in my mind, it was truely a beautiful frame.
Sometimes, its good to take a break from clicking and just enjoy things as they are. At the same time, in my imagination, I never really stop photographing. I endlessly makes frames from the things which I see.