The roadblocks set up by your own mind are just you, lacking right knowledge of your own Mind. Specifically its uncreated substance with its myriad functions, and hence ability, that produces incalculable positions within an arised field of consciousness, when any condition of becoming is ripe.
The most suitable remedy for such a lack of gnosis is to spend a certain amount of singular-time with your true Mind as purely Unborn. This through means of proper Pi-Kuan .
Biological formalities, such as sitting, or standing, or walking, are irrelevant here if the student has a sufficient ability to concentrate properly.
Gazing back on the true imageless [attribute free] nature of your own Mind, vividly all-present right before the interfering field of your eye-consciousness, ear-consciousness or any other consciousness of the senses, is the proper [supra]position of the Pi-Kuan meditator to take refuge in. Where else would this highest and most efficient form of meditating upon the ineffable take place?
What lacks right knowledge of its own true nature is unable to correct, or avoid error and is thus stuck in the Mind´s samsaric realms of endless repetition, through the addictive illusion of apparent variance.
The only way your Mind can have right knowledge of itself, is through the production of its own illuminative wisdom – Prajna, which brings forth the spiritual sentience and reality of the bodhi[sattva].
Without the practice of Pi-Kuan the student of the true Mind will never see the day of any Prajna, and thus forever roam through endless existences without the healing light of bodhicittopada, powerless to the mind numbing forces of delusion and error.
Bodhicittopada or bodhi, is, contrary to those claiming it to be the thought of enlightenment, a most mysterious light, or substance of ineffable beauty and purity, not to be found in this world or any other.
As such it is forever present in the uncreated field of Mind Unborn, yet unknown to all worldlings who are plagued by an abundance of defilements and attachments to all illusions born there-from.
 Pi-Kuan – Chinese. literally meaning wall-gazing or wall-contemplation. The student by effort of Spirit [pure undivided will] uses Pi Kuan as to turn away his Mind’s eye from the interfering consciousness fields of the six senses, and contemplates that which precedes them as a continuous source, which initially is sensed as a dark wall [dark principle] of imageless Mind, Unborn Mind or Mind Only.
This imageless substance of suchness [Tathata] is the body constituting the very Buddha Mind itself, and is thus closer to the student than any field of becoming, thus the absolute reality of his own nature.
Because it is in and of itself Sunya [empty of attributes] it is a most living light, a pure immaculate life-force,Psyche, only sensed by those attuned to its most subtle presence.
A superior student or a student of good virtue and merit can enter Pi-Kuan for short as well as long periods; While waiting for a bus or taxi, sitting in a café, at home, in a cave on some high mountains, or simply performing some good physical exercise like Yoga or martial arts.
The point is, each according to his own ability and gifts, which basically is one’s own merit from practice and acquired knowledge in past existences (including of course the present).