I acknowledge this graphic from the Net.

In this 58th verse ands dharana of the Vigyana Bhairava Tantra, Shiva says:

Sitting or lying, feeling body unsupported

Mind reduced to mindlessness

Let memories dissolve into nothingness

When i study this verse and the dharana, the person who comes to my mind is the Dalai Lama. There is something about him that is weightless, free, liberated, light and mindless. Whether sitting, standing or lying down, he reflects what Shiva says here so effortlessly.  No pretzel poses, no artificiality, no effort at all; he is in the present all the time, time and space irrespective.

How does one go beyond the body and mind?

Shiva says to feel oneself unsupported in body, suspended as it were, and allow the mind to dissolve. he wants us to visualize this, which for most of us is difficult initially.

In order to let go the mind, we need to let go the body. Ironically, letting go mind and body requires that we first become aware of them. In our normal wakeful state of being awake, we think we are aware, but quite unaware. Meditation techniques such as Vipassana and Yoga Nidra create the deep body mind awareness in us. 

A technique I teach, adapted from Vipassana and yoga nidra, and based on a few other Vigyana Bhairava Tantra techniques, is to inhale deeply, hold breath as long as comfortable, exhale completely and then hold in comfort till the next inhalation.

During this cycle, visualize inhaling the energy of the universe into you, hold to expand this energy into every pore of your body rejuvenating , refreshing and recreating you, exhale allowing yourself to dissolve into the energy of the universe, and then hold as you become one with the universe, nothing as well as everything. 

In early days, i used to say expand as one exhales, till a practitioner pointed out that she was dissolving not expanding. She was right. Allow yourself to dissolve into nothingness. Your nothingness of mind and body equates with the completeness of this universe. Sunya becomes purna.

Someone like the Dalai Lama is probably in this state of no mind, all energy all the time. Not all of us may be able to or wish to. Sit for 20 minutes morning and evening and practise this dharana using the breathing technique I outlined. I have a recorded guided meditation for 20 and 40 minutes. If you need, ask.