Achamanam (achamana, achmana) is a Hindu purification ritual in which one sips water 3 times from the Brahma-Grantha (base of the right thumb) while reciting different mantras
As part of sandhyavandanam, achamanam is extended to the purification of the chakras through the touching of certain fingers of the right hand at certain points on the face and body, along with mantras. These are:
Keshavaya Namaha - Thumb to touch the right cheek
Narayanaya Namaha - Thumb, left cheek
Madhavaya Namaha - Ring finger, right eye
Govindaya Namaha - Ring finger, left eye
Vishnave Namaha - Index finger, left side of the nose
Madhusudhanaya Namaha - Index finger, right side of the nose
Trivikramaya Namaha - little finger, right ear
Vamanaya Namaha - little finger, left ear
Shridharaya Namaha - third (middle) finger, right shoulder
Hrishikeshaya Namaha - third finger, left shoulder
Padmanabhaya Namaha - four fingers (hand with thumb folded inwards), navel
Damodaraya Namaha - four fingers, head.
Sankarshanaya namaha
Vasudevaya namaha
Pradyumnaya namaha
Anirudhaya namaha
Purushothamaya namaha
Adhokshajaya namaha
Narasimhaya namaha
Achyutaya namaha
Janardanaya namaha
Upendraya namaha
Hariye namaha
Sri krishnaya namaha
These may be performed whether or not a ritual is to follow; its significance in ritual purification is as valid as "basic" achamanam, and vice versa