The first step in performing a qi gong exercise is to locate the Dantian, a major energy center in the body near the solar plexus. The point is located below the navel at a distance equal to the width of four fingers. The acupuncture point located there is called "Gate to the Original Qi," and the Dantian is located inside the abdomen about a third of the distance between that point and the spine. This is the focus of meditation during qi gong exercises.

When performing qi gong, it's most important to relax and be calm:

After a qi gong session, people typically feel energized and relaxed, ready to deal with the stresses of the world in a calm and grounded manner.

 

source: http://health.howstuffworks.com/traditional-chinese-medical-treatments3.htm