Here’s an exercise Joe taught me.
Three Dan Tian in One – using the mind to direct the qi to target areas
Stand with feet shoulder-width apart. Keep legs straight but knees relaxed. Breathe deeply into the dan tian (three inches below the navel). Relax hands and arms, keeping them at the sides.
Fill the general dan tian with qi while breathing in. When you breathe out, just relax. Repeat the focus on breathing in and building qi until the general dan tian is full. Then move the qi between the other three dan tians as follows:
First send qi upwards to the middle dan tian, which is located on an imaginary line 1/3 of the distance from the Sea of Qi (one and a half inches below the navel) to the Gate of Life (a point directly across from the navel on the back). Take a few breaths there.
From the middle dan tian, send the qi to the upper dan tian, which is the point of intersection of a horizontal line drawn from between the eyebrows to the back of the head and a vertical line coming downwards from the point on the top of the head where the three bones meet. Again take a few breaths there.
Next send the qi back to the middle dan tian, and lastly down to the lower dan tian, located at the perineum (the region between the anus and the genitals). Again take a few breaths there.
Repeat the exercise, sending the qi up to the middle dan tian, then to the upper one, down to the middle again and to the lower one, again and again. As you get more experienced, just take one breath at each dan tian.
After you are good at moving the qi up and down to the three dan tians, coordinate the moving of the qi with the breathing and also with the movement of the eyes and the tongue, so you do the entire upward/downward sequence with one breath as directed below:
As you bring the qi upward from the perineum, slowly breathe in, raising the eyes upward, and touching the roof of the mouth with the tongue. This helps bring the qi upward. As you lower the qi from the upper dan tian, slowly breathe out, lowering the eyes and lowering the tongue from the roof of the mouth to the floor of the mouth. This helps guide the flow of the qi downward. Repeat these movements, inhaling and exhaling as smoothly and evenly as possible. Eventually the movement of the breath, qi, eyes, and tongue all become completely integrated.
The qi moves upward and downward, through all 3 dan tian, with one breath, inhaling as the qi, tongue, and eyes move upward, and exhaling as the qi, tongue, and eyes move downward.
This exercise may also be done sitting or lying down. Practice for 30 minutes daily, paying attention to the smooth and even movement of the qi through all 3 dan tians, coordinated with the smooth and even movement of the breath, eyes, and tongue.
General Dan Tian: 6 fingers sideways or 3 biological inches below the navel. A biological inch is equal to the length of the middle joint of your middle finger.
Sea of Qi: 3 fingers sideways below the navel or one and half biological inches below the navel.
Gate of Life: Directly across from the navel, between the two kidneys, (on the back). When drawing an imaginary horizontal line to the back on the spine, adjust it down a bit as the tendency is to identify the spot a little too high.