The stomach line starts at the side of the nose where it connects to the Large Intestine Meridian.
A branch reaches up the face internally to connect to the inside corner of the eye. It emerges from the bottom of each eye to run down the front of the face to the corner of each mouth. From the corner of the mouth, intenal branches run along the top and bottom gums.
From the corner of the mouth the meridian of the stomach angles back and slightly down to the angle of the jaw. From there it runs up the side of the face, infront of the ear, up to the corner of the forehead.
Note that some charts show the two sides of the stomach meridian linking up at the center of the hair line.
From the corner of the jaw, the stomach meridian runs down the front of the body passing through each nipple, along the outer line of the rectus abdominus, and then from there down the front of the thigh and lower leg to terminate at the top of the end of the second toe.
A branch also extends to the big toe where it connects to the spleen meridian.
Internally, from the collarbone, a branch runs down to connect to the stomach and spleen. From there it rejoins the external branch near the pubic bone.
Another internal branch arises below the knee from where it extends to the middle toe.
The stomach meridian can be stretched in a yoga pose like upward facing bow (urdhva Dhanurasana). It can also be stretched while doing (downward facing) bow pose.
In both postures, you can focus on bending your spine backwards so that the stomach meridian is stretched along the front of the torso.
In upward bow you can focus on pressing your pelvis upwards to stretch this meridian at the front of the hip. Note that because you will probably be using your thighs to help lift your hips and straighten your knee, this actually energizes the stomach meridian at the front of the thighs.
In bow pose you can focus on relaxing your arms and legs as much as possible. Use your spinal erectors to help bend your spine backwards. In addition, relax your shoulders and allow your arms to pull back. Focus on reaching your knees up.
The stomach is positioned on the left side of the body. You can visualize it being positioned below the heart and left lung. It is partially separated from the bottom of the lung by the wedge shape of the liver, which is situated on the right side of the body.
Both the stomach and liver are separated from the bottom of the lungs by the respiratory diaphragm. it is via an opening in the diaphragm that the esophogus passes through the diaphragm to connect to the stomach.
Because the stomach is suspended from the diaphragm by connective tissue, the stomach moves with the diaphragm. When the diaphragm contracts it pushes downwards. As a result, the stomach is pushed down and forwards to the point that it may push slightly under and out from beneath the arch of the ribcage. When the diaphragm is relaxed, it moves upwards, and the stomach moves up with it.
The spleen is to the left of the stomach, also below the diaphragm. The left kidney is just behind it. When visualizing the stomach you need to give room for both the spleen and kidney.
Both the stomach and spleen are related to the element of earth. You can associate with this element the qualities of being grounded or present. You can also imagine this element to be the foundation for all other elements. Associating the other four elements with the four seasons of the year, these seasons all happen because of changes within the earths relationship to the sun.
Because the earth is so big relative to ourselves, it remains unchanged relative to our individual selves. In anything that we do, the better we connect to the earth or the more aware we are of our connection to the earth or how we are positioned relative to it, the better we can do what we are trying to do.
Applying this principle to the relationships within ourselves, in anything that we are doing, if we have a reference, or a stable foundation then we can create the change that we desire.
Focus on two points either side of your nose. Connect these points to the corner of each eye. From the bottom of each eye focus of two lines dropping down to each corner of your mouth. Focus on feeling your upper and lower gums. Next focus on feeling the limits of your face, following the curve of your jaw to each side of your face. Go upwards along each side of your face and then inwards, following the line of your hair to the peakc of your forehead. Focus for afew moments on feeling all of these lines.
Next focus on two lines running down the front of your neck to your collar bones, just outside of the two "balls" that are the connecting point of your collar bones to your sternum. Follow the line of your stomach meridian down the across each of your pectorals and down the outside edge of your rectus abdominus to the front of your pelvis. From there, trace with your minds eye a line down the front of each thigh and shin to the second toe of each foot. Trace these lines a few times and then imagine feeling them "all at once."
Visualize your stomach at the same time.
If you've already learned the lung and large intestine meridian meditations. Inhale along your lung meridians and visualize your lungs at the same time. Exhale along your large intestine and stomach meridian while visualing the related organs.
As a yoga teacher, I'm constantly exploring new exercises, new ways of doing yoga poses.
There is no single "right way" of doing a yoga pose. Instead, there are options. And the better you are at "feeling" your body, the better you can get at choosing the right option for your body as it is now.
For any technique, the point of practice is to learn feel it and to control it, so that it can be used without thinking about how to use it.
And that is more or less the approach taken in all of my ebooks and videos. They help you to feel your body and control it so that you can work towards using it effectively in anything that you do.