Cattāri Brahmavihārā

I bow to the Lord of Compassion!

All sentient beings, my mothers,

wish happiness; all wish to avoid suffering.

If all my mothers suffer, how can this child be happy?

Bless me to take away their suffering.

I take into my heart

all their suffering and the causes of suffering.

ram yam kham

By the fire of aspiration and the wind of compassion,

it dissolves into emptiness.

om ah hum

I give them all my happiness and the causes of happiness.

Bless me to give all gain and victory to them.

I shall suffer the consequences of my unskillful acts,

if not this very day, then shortly after—

bless me to eat the bitter fruit before it ripens.

so’ham sa’ham

Gain and victory to others, loss and defeat to myself!

Whenever and wherever I meet my anguished parents,

bless me to mount this aspiration on the breath.

Mind Training 7 – 9: Formal Practice — Tonglen: Giving and Taking

Train alternately in taking and giving.

Begin close to yourself.

Mount the two upon the breath.

https://greatmiddleway.wordpress.com/2013/04/06/tonglen-giving-and-taking/

RAM YAM KHAM

This is a general and very common purification Mantra. Often found at the beginning of many Tibetan Sadhanas (practice texts.)

Ram is the seed syllable representing fire and red in color – Purifying through burning up all impurities.
Yam is the seed syllable representing air and typically blue in color – Purifying through blowing away impurities.
Kham is the seed syllable representing water and typically white in color – Purifying by washing away all impurities.

Combined we are purifying with fire, water, and air. In this case we are purifying through our speech and our visualizations to all of the immediate surroundings in which we are practicing. As an extension, We are also purifying ourself, others and all surroundings for as far as we can visualize.

OM AH HUNG

This is the resonance of purity of Body, Speech, and Mind.
OM – White in color (like water) and focused at the crown chakra is the sound vibration to purify the body.
AH – Red in color (like fire) and focused at the throat chakra is the sound vibration to purify speech.
HUNG – Blue in color (like the sky/air) and focused at the heart chakra is the sound vibration to purify the mind and thinking.

Through such repetition of the mantra, we are purifying our body, our speech, and our mind. We then maintain the purity of body, speech, and mind at the very least to our practice and ideally beyond to all of the future It is up to us to maintain pure conduct and commitments to maintain the purity.

http://almostdzogchen.blogspot.com/2006/07/ram-yam-kham-om-ah-hung.html