In the foundation level, a practitioner has to generate his initial chi with a pair of stretched hands, with their stretched fingers, equally separated and stretched. It is required in zhan zhuang (standing meditation), seated meditation, and in doing tai chi form, of all schools. The beginning is actually not too complicated, afterall our fingers are the most sensitive chi body parts. A tingling sensation is the most often subjective experience of a beginning practitioner.
When a practitioner's chi gets stronger through practice (how is another issue not being discussed here), the function of the fingers has one added dimension. In addition to chi generation, the stretched fingers has an added function of chi balancing and management. And in these two areas of chi generation and chi balancing, a practitioner has to work with each of his individual fingers separately. And it is in this second level that different practices differ. They differ in the way how they train each fingers of a practitioner. This is how they differ:
1. In Tibetan Buddhism, it is through the use of different and oftentimes look complicated mudras. In Tibetan folk medicine, mudras are also used for healing different bodily ailments. In the past when a poor peasant got ill, he could not afford going to see a herbal doctor for proper treatment, he had to make do with mudras taught by monks with a kind heart. And if he went to see a herbal doctor, the doctor might also prescribe one or two simple mudras to help the healing process.
2. In Taoist Neidan (meditation), it seems that the use of mudra or finger-patterns have not been widely used (there is only one Taoist mudra) but that perception is wrong. The classic Taoist mudra of covering one hand with another is actually a concealed system of versatile mudra, and it also holds the key to understanding what mudra is all about, for all chi-disciplines. With the fingers concealed, a practitioner is taught to focus on one or any combination of his fingers for chi generation and chi balancing. Unlike Tibetan Buddhism, the Taoist way does not have any fixed pattern. But how does a practitioner know what to do? The answer is that a practitioner is expected to feel chi himself and therefore is expected to be able to generate different chi by focusing on different fingers (or finger combinations) and will be expected to balance his chi accordingly, using his differently focused fingers.
3. In tai chi, the use of individual fingers has often been overlooked. The most often used method is making a powerfully stretched claw to train total muscles strength (e.g. 24 styles tai chi neigung: tiger claws), or claw with index and middle finger outstretched (e.g. QiChuen style). Understandably more for muscles strength than for healing. There is however one master who taught how to use individual fingers in tai chi for healing or health benefits, it is late Wu-style tai chi aaster Wu Tunan (吳圖南). Master Wu taught his students to use each finger (left and right at the same time) separately as leading guide to do tai chi forms (hence, using all five fingers will require doing the tai chi form five times).
As with other things in Qigong, the methods are quite simple, as my readers can see from the above. The only difficulty is to have the patience and the focus to build one's chi sensitivity step by step. In Taoist method, a practitioner is specifically require to do it. Without this key understanding, doing complicated mutras or doing the form with finger leading will seem rather silly for a practitioner, and needless to say, without much benefit.