The following article appeared in the childrens category of Shri Shakti Darshan magazine, explaning the technique and benefits of Trataka meditation in a question/answer format.
Ammu: What is Trataka?
Annu: It is a simple exercise to increase concentration. It is also called flame concentration test, or candle concentration test. Sit in any comfortable position and place a lamp or candle 3 feet in front of you at the same level of your eyes. Ensure that there is no wind so that the flame will not fickle and will be steady. Just stare at the flame without winking the eyelids till tears start rolling down. Then close your eyes and place your palms on the closed eye lids and concentrate on what appears through the closed eye lids.
You can see the flame in different colors. Just enjoy the vision till it slowly fades away. Usually people can stare at the flame for 3 to 5 minutes and see the image for another 2 minutes.
Ammu: Is it not harmful to the eyes?
Annu: Not at all, instead is an exercise to the eye. The eye muscles contract and remain in the same position during that time. When you close the eyes, the muscles relax.
It is just like doing your yogasana or jogging. The power of accommodation of your eyes increases. Secondly as you will be concentrating only on the flame, mind will be at peace and your concentration power increase.
Ammu: When this is to be done?
Anu: In the early morning or in the evening when there is still darkness. In the bright day, flame will not be visible clearly. If the outside is very dark, the flame will appear to be very bright and the eyes will get tired soon. In your pooja room also you can practice it, as there will be usually dull light.
Ammu: I shall try it today itself.
I would like to add some of my views here. As concentrating on the flame increases heat in the eyes, it is necessary to cool the eyes, by washing the eyes with cool water or rose water, after performing the above exercise.