Excerpted from http://www.arunachala-ramana.org/news_self_enquiry.htm since the link has changed and could change again:
First and foremost Bhagavan stated that self-enquiry should be performed with the same intensity as that of a drowning man struggling for air, only then can it succeed.
Self-enquiry is holding on to the awareness of being that ‘you already are’. There is only one awareness, the one who is reading this article is the ego and the Self all in one, but the ego is the apparition covering the pure Self and that has to die to the real Self in order that self-realisation can take place. This is a mystery at first, but once accomplished it is very clearly understood.
Bhagavan often made the comparison of the actor in a Play - during the Play the actor assumes a completely different role, yet retains his true nature and combines the two. A good actor truly believes he is the role that he is playing, but after it is finished he discards the role and reverts to his original nature. In our case we have forgotten who we are and believe that our role is the reality. Just as the actor is not two Beings, not two ‘I’s’, nor are we two ‘I’s’. It really is that simple. However, our ingrained belief that the role we play is in fact the Reality is so strong, that it requires intense and prolonged effort to remove it.
To do this you must concentrate totally upon the awareness of ‘you’, without thought of any kind, or (alternatively) try to catch the ‘I-thought’ as it rises from within and then hold on to that firmly to the exclusion of all else.
The ‘I’ thought that you have to catch is a tangible and distinct force that rises from within the apparition created by the ego. It is this force that sustains the apparition and gives it life, just as the actor gives life to his part in the play through his own personality. There is however an acute difference. The pure ‘I’ thought is devoid of personality as we normally understand it – it just IS. This process requires intense, unbroken concentration, and in the majority of cases takes many years of hard effort and should be carried out, if possible, with eyes open. This does not involve physical or emotional strain of any kind, and strain should always be avoided.
When successful, awareness withdraws from the body into the crown of the head – this is usually very fast and experienced as receding from the feet upwards. At this point the breath becomes automatically controlled separate from that awareness of ‘being’ and it might even stop altogether. Even in this minor stage there is no concern whether the breath stops or not, because the body is already perceived as a heavy, cold and totally lifeless thing, not ‘you’, but something alien to you, a burden that you do not want. The awareness focussed in the crown of the head is however pristine in clarity and thought is suspended. This expansion of consciousness though devoid of bodily attachment is still the dark ego/mind complex.
At this point and in all of the following experiences the attention should be carefully, but powerfully turned towards the witness of all of this, with an intense thought-free longing to know who it is that sees it. The focus of attention will now move to the nape of the neck and then after further enquiry to the middle of the spine above the solar plexus, but the body and outer world are still apparent, though dreamlike.
Once again attention must be turned back to the one who witnesses all of this and it is at this point that a full expansion of consciousness takes place and the awareness moves to the so-called heart-centre, which is NOT within the body. This heart-centre is the seat of dark ignorance, the point from which the ego rises. The body, world and everything else has now vanished, to be replaced by a perception of vast energy proceeding forth to give rise to the universe. This energy is perceived as darkness, a profound ignorance covering the light of Pure Being, but is arising from ‘you’, the witness, and it is to that source that the attention has to be turned and the enquiry continued. This is the point reached by those who experience the stars and the universe withdrawing into them, it is not the finality, not self-realisation, merely one more illusion, but a very powerful one.
When attention is once more silently focussed on the one who witnesses all of this, the final stage of the enquiry takes place. The transition through the knot of ignorance at the heart-centre is accomplished and the purity of the unlimited deathless Self is known. Yet even here at the fifth stage of the quest the mind remains potential. The light of pure consciousness is perceived, but it is still only ‘perceived’. This is NOT self-realisation, but a very seductive state to remain in for those who seek the finality.
Only when this final stage is transcended is Self-realisation complete. This cannot be accomplished by the same enquiry as the previous steps, but only by complete surrender, the total dissolution of the mind into the ‘being-consciousness-bliss’ of the One Reality. This is in fact the most difficult, yet the easiest of all; how it is accomplished can be understood only when it is reached.
Bhagavan Sri Ramana Maharshi remained permanently in the Supreme State. It is the state of Supreme Solitude, where death is an impossibility, where time and timelessness are one, where a billion years and a fraction of a second are the same, where immeasurable energy and absolute stillness are one, where difference is impossible and bliss alone is. Where light brighter than a billion suns pervades all, yet pervades nothing, where awareness of Being, beyond measure, pristine and unchangeable is known as you! This is the supreme state … your true state! It is not a void, but is immeasurably full, it is pure awareness, pure Being, perfect bliss, without beginning, middle or end. You are all of That and more!
To overcome the cycle of birth and death this latter state has to become permanent, and nothing less should be accepted by the true seeker.Bhagavan’s death experience is a clear pointer to the method of enquiry, but the English version published so far is a far cry from the reality of it. Krishna Bhikshu continuously verified the accurate version with Bhagavan over many years (in Telugu) and nowhere in that version is it mentioned that Bhagavan mimicked a corpse.
The complete article lies here.