According to Kundalini Yoga, we relate to the universe in the form of Shakti or dynamic feminine energy. This Shakti exists within ourselves in the form of the goddess and is called Kundalini. This Kundalini can be thought of as the inner manifestation of the divine mother. Within our bodies, the dormant Kundalini sits at the base of the spine in the Muladhara Chakra.
There are two phases of Kundalini awakening:
The purification phase is practiced over a longer period of time and very important. Generally, for the purification phase, we practice several techniques of Hatha Yoga such as pranayama, asanas and kriyas.
For the awakening phase, we practice more advanced pranayamas, mudras and bandhas, which move the Kundalini from its seat in the base of the spine, ever progressively upwards through the Sushumna Nadi and the Chakras, until the Kundalini reaches the Sahasrara Chakra at the top of the head. Sometimes this is called the union of Siva and Shakti.
Only by purifying the nadis and awakening these 7 main Chakras is the Kundalini able to rise up through the spine. As the Kundalini ascends through the various chakras, various siddhis, or yogic powers will manifest. Many yogis, not as pure as they should be, have been ruined by the manifestation of these unchecked powers when they tried to awaken Kundalini before they were ready. It is because of this that the groundwork of purification and practice of the yamas and niyamas must be well established prior to Kundalini awakening.