I was taught this Kundalini mantra by a friend to help me ground myself. Now I do it when I'm upset, when I feel my blood pressure rise, when I feel dizzy, etc and it works in a matter of seconds.
The Grounding Excersize
With both hands, press your thumb to your forefinger and say "Sa" (pronounced S-ah), then your middle finger and say "Ta" (pronounced Tah), your ring finger and say "Na" (pronounced N-ah), then pinky/little finger and say "Ma" (pronounced Mah) then back to fore finger and work your way through the procession again.
You do not have to say the mantra out loud for it to work so this simple exercise can be done in public, at work, where ever.
This works with the meridians of the body and by pressing each finger to the thumb is representative of pressing each element in the body to the earth element (the earth meridian resides in the thumb), thus grounding them.
The Sounds
SA TA NA MA represent the words Sat Nam, which is the bij mantra or seed mantra. It is the mantra that sows the seeds of truth in our consciousness. The sounds of the mantra, Sa Ta Na Ma, connect consciousness to the evolution of existence itself and can be transformational when used regularly with meditative practices such as Kundalini yoga.
Sa represents both beginnings and infinity - all that ever was or will be.
Ta is life, existence, creativity.
Na represents death and change
Ma is rebirth
SA TA NA MA is said to help not only ground and lead towards transformation but can be used to break bad habits and addictions because it strongly effects the subconscious mind.