Mudra signifies gesture or even a symbol. Gesture can effectively engages and influences the body and mind by bending, crossing, extending or touching the fingers with others fingers.
How to do Prana Mudra : place the tips of the thumb, ring finger, and little finger together. The other fingers remain extended.
This gestures activates the root chakra, in which elemental force of human being is found.
I like to use it while practising Warrior 2 and other asanas (poses) Its grounds me and sets my intention and integrity towards strength and courage when I need it.
Prana Mudra generally increases vitality, reduces fatigue and nervousness. Also improves vision. On a mental-emotional level, it increases our staying power and assertiveness, healthy self-confidence, gives us the courage to start something new and the strength to see things through (clearly structure thoughts and ideas)
The Prana Mudra combined with a conscious, slow and gentle way of breathing has the effect of being a stabilizing and calming as a secure anchor.