Kumbhaka is the central practice of traditional Hatha pranayama; there are two types of retention in this breathing practice: after an inhale (antara), and after an exhale (bahya) The Sanskrit word kumbha translates to “pot” (a traditional image of the human torso as a container for the breath with two "openings" at the throat and base of the pelvis).
Before you begin, establish several cycles of Ujjayi breathing (gentle constriction of the back of your throat). To begin, apply the two bandhas as you near the end of your inhale, and retain the breath inside for a count of 3-5. Gently squeeze the ribs against the expanded lungs. Then exhale all of your breath through your nostrils as you draw the contents of your low belly up and in. Continue to suspend your exhale for a count of 3-5. Continue these slow and conscious cycles of sealing in your inhalations and suspending the breath out on your exhalations.Now start to reduce the number of Ujjayis between the cycles of breath retention until you can comfortably retain your breath for a count of 3-5 on successive inhales for about 5 minutes. Next increase your breath retention, while continuing to separate the rounds by 2 to 3 Ujjayi breaths.
While engaging in this pranayama exercise, take note of that infinite space in between your inhalations and exhalations. Acknowledge how much more enriched your breath becomes when you are consciously creating a pausing in between each cycle of breath. You may start to notice that your inhalations become deeper, more nourishing. And your exhales may become richer and more detoxifying.