aShTAnga yoga means the yoga with eight limbs/bodies. The aShTAnga yoga prescribes an eight step way to achieve the ultimate Union. These are progressive in nature, starting from the simple day to day discipline recommended by most religions to the highly advanced Yogic practice and the enjoyment of Bliss. This is a wonderful concept that stands to show the maturity of the spirituality in Hinduism - Shaivism.
The eight steps are:
These are the basic discipline that qualifies one for the subsequent elevation. This include "not killing, truth, not cheating, humility, neutrality, sharing with others, purity".
This is the chosen spiritual service that is accepted by one as the motto in life. These are the rituals of worshiping the Lord Shiva. This include austerity, chanting, happiness, trusting God, charity, shivavratas, philosophy seeking, rites, worship of shiva, seeing flame.
For the yogic practice the posture of the body is quite important. Hence this is given a separate level in the ladder. One would have to practice these posture and get comfortable with. There are many such Asanas.(2) The famous ones being padmAsana, sukhAsana, badrAsana, kukkuTAsana etc.
The breath is the key element that controls the waves of thoughts. So the control of the breathe assumes a good amount of significance. The scriptures prescribe how to breathe in ( pUraka ), keep in ( kumbakam ), and breathe out ( rechakam ) and what are the suggested durations. Things get quite simplified when the mantras are chanted during this prANAyAma, whose syllables are proportional to the duration of the timescale for each action.
This is the stage of bringing the focus of the mind to internal. The mind which is wandering around on the external things is drawn back carefully and made to look internally. The base of kuNDalini is felt at this stage. The practitioner rejoices and melts in the Supreme Flame inside.
Making the mind stay steady, which was drawn inwards by pratyAhara. The great power that resides at the base point of mUlAdhAra is carefully raised through the susumna chord by contemplating carefully.
Making the mind focus without any breaks. In dharaNa the mind gets steady but not continuously focused. In meditation (dyAnam) the mind gets fixed and continues in that state.
This is the ultimate step of the aShTAnga yoga. A non dual union occurs.