What is the goal? To escape mental habits and tendencies which have become excessively ingrained and therefore mistaken as aspects of reality as opposed to modes of perception. The goal is to be open to all possible perspectives and experiences including those radically different from the ordinary human experience.
The goal is to cease to be a human? You’ve never been a human. The goal is to cease believing that you are a human.
Why is it preferable to cease believing you are a human? Firstly, because it is incorrect. Secondly, because the human body is limited. It will suffer, age, and then die. You will undergo all of these experiences and they will be painful, unless you realize that they are not happening to you, you are merely experiencing their happening. It is essential to come to hold the right view about the nature of your experiences.
What is the right view? The right view is to understand one’s experiences exactly as they are, to penetrate their nature. Right view is to perceive the physical world as a dream, a fabrication, an illusion, not ultimately real. This means one drops the beliefs they hold in normal, waking life about the nature of their experiences (i.e. as happening in a real, physical, external world) and adopts another. Right view is distinct from wrong view, or the conventional human mode of consciousness, in the same way that a painter presented with an apple would react differently (on instinct, immediately, without contemplation) than a starving man: phenomena are perceived in an entirely different way, despite being, superficially, the same phenomena. Right view is when the understanding of subjective idealism is consciously evident in the nature of one’s experiences. This is the difference between understanding “I’m typing on my keyboard right now” and “I’m experiencing Utthana typing on his keyboard right now” and having such an understanding as it is happening.
That's a nice concept in theory, but maintaining that mode of experiencing all day is an act of meditative endeavor. How is this achievable? It’s true that this is to be attained through right mindfulness, or right meditation, which is an endeavor. But constant endeavor is necessary to be ultimately flexible.
Wait, why is it desirable to be ultimately flexible? One who is flexible, adaptable, and comfortable with all experiences is immortal, invulnerable, and infinitely powerful. One who is ultimately flexible is one who is open to all possible experiences.
This now seems even more daunting! The ability to instantly, attentively, alertly, and consciously respond to each experience individually and uniquely is what it is to be enlightened. This requires a mind (“The Beginner’s Mind”) which is open, unattached, and pliable, accommodating to every farthest reach of conceivable experience. The mind must not be dull, unaware, lost in thought, lost in action, “being human”, full absorbed in the physical world and taking it to be real, in a “normal state”.
What does this have to do with mindfulness or meditation? Only when one is attentive to every possible type of experience can one be expected to react to, and respond to, each with the full alertness, attention, and conscious awareness to be ultimately flexible. If you are not aware of each experience you are having as it is, you will never be able to respond to each skillfully and with an open heart. You will, instead, fall back into old patterns and default, human ways of perceiving things (i.e. physicalism).
So how is this to be achieved? Only by being constantly vigilant can this be achieved. One must arouse one’s self to full attention of the experience that one is undergoing according to the Right View. This is the difference between being able to say, “I just walked across the room,” and having been intensely aware of the fact that you were experiencing yourself walking across the room during each instant of your walking.
This still sounds like a strenuous meditative endeavor. Am I expected to be completely alert to my experiences all day and every day? Yes. The normal, waking mode of consciousness is when one is capable of discussing subjective idealism theoretically but, for fifteen hours a day, experiences itself as human, busy with tasks, mind not fully aware of the nature of one’s experiences but instead lost in interaction, conversation, and the physical world. The mode of consciousness that is desired is when one is, instead, constantly aware and alert to the nature of their experiences, ultimately flexible, not lost in thought or busy with tasks, not experiencing itself as human. Every minute, every hour, every day, every lifetime not spent completely alert and attentive is a minute, hour, day, or lifetime spent ingraining conventional habits.
Is the maintenance of such a state not exhausting? No. The samsaric state of being lost in ordinary thoughts is where we are comfortable, and it is a strain and difficulty to become constantly aware and alert. But this is not a perpetual endeavor, like a mental task of thinking of the same mantra over and over, day in and day out forever. This is a shift from one natural resting place for the mind to another. Once one “gets into the habit” of perceiving reality with full attention and awareness and not allowing the mind to get lost, remaining in such a state becomes as natural as remaining in the normal, waking mode of consciousness is to us now. The alert, awake mode of consciousness can become how one wakes up, the mode one defaults to in events of trial and trauma (including death), and even how one dreams.
Never mind maintaining it, how does one initially get into such a state, or return to such a state after one has relapsed to the normal, physicalist perception? There are many ways. Intense and prolonged contemplation on right view is often sufficient to induce the shift in the character of experiences, but the practice is not entirely 'passive'. Meditation or drugs, when done by one who has firmly grasped the right view, can induce this shift. Active and intentional magickal practices can be exceptionally powerful tools as well. But the real trial lies in the maintenance of right view and right mindfulness throughout all of life. The difference between one who theoretically understands wisdom for a few hours of the day, and one who lives with wisdom even in their dreams, is the effort undertaken to maintain that state of consciousness. Being intensely aware of one's experiences exactly as they are happening, in the context of a latent understanding of right view (subjective idealism), and maintaining such a state, is all that is necessary.