To start, focus on learning the meridians and some of their key points located near joints of the limbs:
Once you get a sense for the paths of some meridians you can begin to work with them at a physical level (tap, press, stretch). And then, gain mastery at an energetic level (directing qi through the channels using progressively more advanced qigong techniques). In terms of the Neidan yoga model, this corresponds to the foundations and weigong (outer qigong) levels. Your goal should be to understand the 14 major meridians, their major points and how to course qi (prana) along the channels in conjunction with qigong exercises. As an exemplar, consider the Pericardium (PC) meridian shown at the right. You would work along the blue line from the chest (PC 1) down along the arm to the tip of the middle finger (PC 9).
The next stage, neigong (inner qigong) ties such skills to energy flows inside the body (related to meridians). In the picture to the right, the dotted orange line from the navel up to the heart and over across to PC 1 travels deep inside the body and not on the skin at its surface. Inner flows, such as this, exist for all the meridians. Further work at the neigong level meshes meditation (especially mantra practice) with these inner qigong techniques. Having mastered such skills, a dedicated practitioner may then safely turn toward orchestrating the streams of energy raining down from the higher ground of Jyotish archetypes.
Chakras and Rāśis
As you probably know, chakras represent energy centers along a central channel deep inside the body that runs vertically from the bottom of the torso to the top of the head. Some folks and traditions just go for the gold and try to spark the chakras and energies of the central channel. Many traditions, however, take a more circumspect approach and first develop facility with off-midline energy flows. For instance, Daoism advocates learning weigong techniques and then a preparatory qi flow (microcosmic orbit) on the midline but along the surface of body (front and back). Likewise, in Hindu yoga, the classical approach begins with breathing techniques (prāṇāyāma) that adjust off-midline nāḍīs (channels) called the iḍā (left channel) and piṅgala (right channel) which are near to the suṣumṇā (central channel). With such prowess in hand, a seeker may then earnestly commence the task of activating the chakras.
In Neidan yoga, this phase relates to the end of neigong and beginning of neidan (inner elixir). The overarching aim now? Gain a deeply felt sense of the energetic relation between Jyotish archetypes and meridians. How to do this? Apply the basic principles of Jyotish. Here's an illustration:
One key rule of Jyotish covered earlier (refer to Guru in the Lagna) helps to promote health for an individual regardless of what the higher realms may be up to—storm, hail, puffy clouds or clear, blue sky. However, a person may be healthy and still down and out or broke so it's wise to tidy up relations with society and other outer influences on daily living (refer to Path to Light — Arudha Lagna). In Vedic astrology, a chart with the arudha lagna (AL) as its first house furnishes the needed vantage. From here, one finds the jata graha (planet that is kendra to the moon and kona to the AL). If strong, this planet augers well for material and social success. One way to help encourage such a delightful outcome comes by strengthening the two planets that rule the signs where the jata graha is exalted and debilitated.
In this example, the rectangle outlined at the top shows the location of the AL. The rules to find the jata graha determine that the moon itself (labeled as Mo) is this important planet. So, for this individual, success in the world depends upon how supported his moon energy can become. The two numbers circled in orange give the locations of the moon's exaltation (2 = Taurus) and debilitation (8 = Scorpio). So, the two planets that rule these signs (rāśis) are Mars (Ma) and Venus (Ve). How to make them stronger and better? Several choices offer themselves and a full session would include them all. For instance, a planet could be empowered in the sign where it resides (Ve in 10 = Capricorn) or the sign that is ruled could be harmonized (Ve rules 2 so balance Taurus energy).
Got the general idea? There are plenty of good resources for you to learn the theory. What's more important for you to realize at this stage is that such a remedy is possible and can work really well. Since planets and signs (constellations) all map directly to the acupuncture meridian system which in turn maps to the chakras, the actual energy work consists of outer and inner qigong for the relevant meridians and chakras. Mantra and meditation need to be part of this work. Typically, a meditator would run qi along the relevant regions while saying a mantra for a fixed period. Then, she would meditate on the regions and then continue in similar fashion swapping sections of energy work with more formal meditation. A similar style of practice can be applied for other key Jyotish rules and archetypes to round out an important part of yoga at the neidan (inner elixir = cultivating midline energy) level. Here are some more important patterns that get balanced and strengthened:
natal chart (D1) lagna
navāmśa (D9) lagna
Guru (Jupiter) in lagna
kārakāmśa (this is the navāmśa sign in which the ātmakāraka is placed; this sign is set as the D9 lagna and analyzed for all matters of the soul)