The sadhak should realise that his meditational object is not merely a photograph, but a platform for the descent of the Divine.
He should understand throughout everything that the more he concentrates on the picture, the clearer his Ishtam will become. Let it become a truth of his mind that his Ishtam is everywhere, even though he is encased in a body for the favour of his bhaktas. The first and the last truth is that he should constantly be aware of the fact, that there is every truth in the saying; "He will appear before thee in flesh and blood, reveal unto thee jnana, and converse with thee".
When all vrittis pertaining to external experiences have subsided, and when one single vritti is prevailing throughout everything, then the sadhak attains the pure stage of meditation. And when this stage of a single vritti alone continues, and no other thought or vritti is felt in the least, then one is said to have attained samprajnata samadhi. When the entire consciousness of the sadhak is transformed into the form of the Ishtam to the extent that he is seen clearly, the ever glowing darshan is known as samprajnata samadhi.
In the first stage, the form is seen as you see the picture. It means that you are still conscious of the external world. As soon as the awareness becomes single, and the feeling of love reaches its highest stage, and no other than the beloved is remembered, then the immortal form of Ishtam manifests before you as truly as you would like him to be. In fact, all this takes place in the state of wholesale merger and non-dual awareness. The form is the same one you know, but so far you were not able to see on account of sensual and mental limitations. Now that you have reached that stage, where your atma has become all-pervading because of the absence of sensual and mental limitations, you are able to see him.
As soon as the form is apprehended, he enters in the form. He is in front of you in that familiar swaroopa you meditated upon. He is conscious, yet he sits or stands quietly. You keep on looking at him and he at you. This takes time. When you have looked at him for some time, emotions bubble forth, tears flow down and mechanically you fall down at his feet.
The sadhak should see that form continuously for not less than seven days. On the following day of manifestation also, he should sit for meditation as usual, but instead of meditating on the photo, he should bring into his mind the scene of manifestation, and thus awaken his awareness- This process should be continued, so long as the deity does not come to you at any place instantaneously. If you are able to see him at any time you wish, then you should start conversing with him, and praying unto him.
No sooner will you sit for meditation at this stage, than you will see him in his usual posture in front of you. You look at him and he at you. Suddenly you break into emotions and bow down at his feet. He blesses you and disappears. Now you come down to physical consciousness and faintly remember the experience as if it were a distant dream. Joy and ananda become boundless. The mind becomes calm, quiet and serene. The power of magnetism grows intense. The voice grows sweet. Your prayers are fulfilled and your questions answered. Beware that you do not exploit this achievement for personal ends.
There comes a stage where the lower self is completely transformed and fluctuations (mental screens) are torn apart. Pure atma bhav dawns. The sadhak becomes a siddha-master of his mind, tenses and body-Knowledge emerges spontaneously, revelation after revelation. He becomes powerful, full of wisdom, a kalpa vriksha, and a fit receptacle for Brahma anubhava, which is his final goal.