The following is sourced from: http://www.wvi.com/~campb1/24RulesOfQigong.php ...although the creators of that webpage are likely not the authors of the following document. The "24 rules" have been used by multiple authors and the ideas can in a way be considered public domain. The suggestions below may seem a little obscure, or need some further translation, but valuable observations can still be made.
THE TWENTY-FOUR RULES FOR QIGONG PRACTICE
In this section I will list the twenty-four rules which have been passed down by generations of QiGong masters. These rules are based on much study and experience, and you should observe them carefully.
1. Don't be Stubborn about Plans and Ideas
This is one of the easiest mistakes for beginners to make. When we take up QiGong we are enthusiastic and eager. However, sometimes we don't learn as fast as we would like and we become impatient and try to force things. Sometimes we set up a schedule for ourselves: today I want to make my Dan Tien warm, tomorrow I want to get through the tailbone cavity, by such and such a day I want to complete the small circulation. This is the wrong way to go about it. QiGong is not like any ordinary job or task you set for yourself -- YOU CANNOT MAKE A PROGRESS SCHEDULE FOR QiGong. This will only make your thinking rigid and stagnate your progress. EVERYTHING HAPPENS WHEN IT IS TIME FOR IT TO HAPPEN. IF YOU FORCE IT, IT WILL NOT HAPPEN NATURALLY.
2. Don't Place your Attention Indiscriminately When you practice.
do not place your attention on the various phenomena or sensations which are occurring. Be aware of what is happening, but keep your mind centered on wherever it is supposed to be for the exercise you are doing. If you let your mind go to wherever you feel something "interesting" happening, the Qi will follow your mind and interfere with your body's natural tendency to rebalance itself Do not expect anything to happen, and don't let your mind wander around looking for the various phenomena. Furthermore, don't start evaluating or judging the phenomena, such as asking "Is my Dan Tien warmer today than it was yesterday?" Don't ask yourself "Exactly where is my Qi now?" When your mind is on your Qi, your Yi is there also, and this stagnant Yi will not lead the Qi BE AWARE OF WHAT IS HAPPENING, BUT DON'T PAY ATTENTION TO IT. When you drive a car, you don't watch yourself steer, work the pedals and shift gears. If you did, you would drive off the road. You simply put your mind on where you want to go and let your body automatically drive the car. This is called regulating without regulating.
3. Avoid Miscellaneous Thoughts Remaining on Origins
This is a problem of regulating the mind. The emotional mind is strong, and every idea is still strongly connected to its origin. If you cannot cut the ideas off at their source, your mind is not regulated, and your should not try to regulate your Qi. You will also often find that even though you have stopped the flow of random thoughts going through your mind, new ideas are generated during practice. For example, when you discover that your Dan Tien is warm, your mind immediately recalls where this is mentioned in a book, or how the master described it, and you start to compare your experience with this. Or you may start wondering what the next step is. All of these thoughts will lead you away from peace and calm, and your mind will end up in the "Domain of the Devil." Then your mind will be confused, scattered, and very often scared, and you will tire quickly.
4. Shen Should not Follow the External Scenery
This is also a problem of regulating the mind (Shen). When your emotional mind is not controlled, any external distraction will lead it away from your body and to the distraction. You must train so that noises, smells, conversations and such will not disturb your concentration. It is okay to be aware of what is happening, but your mind must remain calmly, peacefully and steadily on your cultivation.
5. Regulate your Sexual Activity
You should not have sexual relations at least 24 hours before or after practicing QiGong, especially martial or religious QiGong. The Essence-Qi conversion training is a very critical part of these practices, and if you practice QiGong soon after sex, you will harm your body significantly. Sex depletes your Qi and sperm, and the Qi level in the lower portion of your body is lower than normal. When you practice QiGong under these conditions, it is like doing heavy exercise right after sex. Furthermore, when your Chi level is abnormal, your feeling and sensing are also not accurate. Under these conditions, your Yi can be misled and its accuracy affected. You should wait until the Chi level regains its normal balance before you resume QiGong. Only then will the Essence-Qi conversion proceed normally and efficiently. One of the major purposes of QiGong is to increase the Essence-Chi conversion and use this Qi to nourish your body. Once a man has built up a supply of Qi, having sex will only pass this Qi on to his partner. As a matter of fact, many QiGong masters insist that you should not have sex three days before and four days after practice. During sexual relations the female usually gains Qi while the male loses Qi during ejaculation. The woman should not practice QiGong after sex until her body has digested the Qi she has obtained from the man. There are certain Taoist QiGong techniques which teach men how not to lose Qi during sexual activity, and teach women how to receive Chi from the man and digest it. We will leave the discussion of this subject to QiGong masters who are qualified and experienced in it.
6. Don't be Too Warm or Too Cold
The temperature of the room in which you are training should not be too hot or too cold. You should practice in the most comfortable environment which will not disturb your mind or cultivation.
7. Be Careful of the Five Weaknesses and Internal Injuries
Five weaknesses means the weaknesses of five Yin organs: the heart, liver, lungs, kidneys, and spleen. When you realize that any of these five organs is weak, you should proceed very gradually and gently with your QiGong practice. Chi Gung practice is an internal exercise which is directly related to these five organs. If you do not move gradually and gently, it is like forcing a weak person to run 10 miles immediately. This will not build up his strength, instead it will injure him more seriously. For the same reason, when you have an internal injury your internal Qi distribution and circulation is already disturbed. If you practice QiGong your feelings may be misled, and your practice may worsen your problem and interfere with the natural healing process. There are specific QiGong exercises which are designed to cure internal injuries, but to use them properly you need to have a very good understanding of the Qi situation in your body.
8. Avoid Facing the Wind when Sweating
Don't practice in the wind, especially facing the wind. When you practice QiGong you are exercising either internally, or both internally and externally. It is normal to sweat, and since you are relaxed, your pores are wide open, If you expose your body to cold wind, you could become ill.
9. Don't Wear Tight Clothing or Belts
Always wear loose clothing during practice because this will help you to feel comfortable. Keep your belt loose, also. The abdomen is the key area in QiGong practice, and you must be careful not to limit the movement of this area because it will interfere with your practice.
10. Don't Eat too Much Greasy or Sweet Foods
You should regulate your eating habits while you are practicing QiGong. Greasy or sweet foods will increase your Fire-Qi, making your mind scattered, and your Shen will stray away from its residence. You should eat more fruits and vegetables, and abstain from alcohol and tobacco.
11. Don't Hang Your Feet off the Bed
In ancient times the most common place in QiGong practice was sitting on your bed. Since most beds were high, if you sat on the edge of the bed your feet would hang off the side of the bed above the floor. When you practice QiGong your feet should touch the floor. If they do not, all of the weight of your body will press down on the lower part of your thighs and reduce the Qi and blood circulation. Furthermore, when you practice you should not put your feet up on the table, because this position will also stagnate the Qi and blood circulation.
12. Don't Practice with a Full Bladder
You should relieve yourself before starting your practice. If you need to urinate during practice, stop your practice and do so. Holding it in disturbs your concentration.
13. Don't Scratch an Itch
If you itch because of some external reason, such as an insect walking on you or biting you, do not be alarmed and keep your mind calm. Use your Yi(mind) to lead the Qi(energy) back to its residence, the Dan Tien. Breathe a couple of times and gradually bring your consciousness back to your surroundings. Then you may scratch or think of how to stop the itching. However, if the itching is caused by Qi redistribution in the QiGong practice, remain calm and do not move your mind there. Simply ignore it and let it happen. Once it has reached a new balance, the itching will stop. If you scratch this kind of itch it means that your mind has been disturbed, and also that you are using your hands to interfere with the natural rebalancing of your body's Qi.
14. Avoid Being Suddenly Disturbed or Startled
You should avoid being suddenly disturbed or startled. However, if it does happen, calm your mind. You must absolutely prevent yourself from losing your temper. What has happened has happened, and getting angry will not change anything. What you should do is prevent it from happening again. Most important of all, though, is learning how to regulate your mind when you are disturbed.
15. Don't Take Delight in the Scenery
It is very common during practice to suddenly notice something that is going on inside of you. Perhaps you feel Qi moving more clearly than ever before, or you start to sense your bone marrow, and you feel elated and excited. You have just fallen into a very common trap. Your concentration is broken, and your mind is divided. This is dangerous and harmful. You must learn how to be aware of what is happening inside you without becoming excited.
16. Don't Wear Sweaty Clothing
This happens mostly in moving QiGong practice, especially in Martial QiGong training. When your clothing is wet from sweat you will feel uncomfortable, and your concentration will be affected. It is better to change into dry clothing and then resume your practice.
17. Don't Sit When Hungry or Full
You should not practice QiGong when you are hungry or when your stomach is full. When you are hungry it is hard to concentrate, and when you are full your practice will affect your digestion.
18. Heaven and Earth Strange Disaster
It is believed that your body's Qi is directly affected by changes in the weather. It is, therefore, not advisable to practice QiGong when there is a sudden weather change, because your practice will interfere with your body's natural readjustment to the new environment. You will also be unable to feel and sense your Qi flow as you do normally. You must always try to remain emotionally neutral whenever you practice QiGong; even if you are disturbed by a natural disaster like an earthquake, you must remain calm so that your Qi stays under control.
19. Listen Sometimes to True Words You need to have confidence when you practice QiGong. You should not listen to advice from people who do not have experience in QiGong and who are not familiar with the condition of your body. Some people listen to their classmates explain how they reached a specific level or how they cured a certain problem, and then blindly try to use the same method themselves. You need to understand that everyone has a different body, everyone's health is slightly different, and everyone learns differently. When the time comes for you to learn something new, you will understand what you need. Play it cool and easy, and always have confidence in your training.
20. Don't Lean and Fall Asleep
You should not continue your QiGong practice when you are sleepy. Using an unclear mind to lead Qi is dangerous. Also, when you are sleepy your body will not be regulated and will tend to lean or droop, and your bad posture may interfere with the proper Qi circulation. When you are sleepy it is best to rest until you are able to regain your spirit.
21. Don't Meditate When You Have Lost Your Temper or Are Too Excited
You should not meditate when you are too excited due to anger or happiness. Since your mind is scattered, meditation will bring you more harm than peace.
22. Don't Keep Spitting
It is normal to generate a lot of saliva while practicing QiGong. The saliva should be swallowed to moisten your throat. Don't spit out the saliva because this is a waste, and it will also disturb your concentration.
23. Don't Doubt and Become Lazy
When you first start to practice QiGong, you must have confidence in what you are doing, and do not start doubting its validity, or questioning whether you are practicing correctly. If you start doubting at the beginning you will become lazy, and you will start questioning whether you really want to continue. In this case, you will not have any success and your practice will never last.
24. Do not Ask for the Speedy Success
This is to remind you that QiGong practice is time consuming and progress is slow. You must have patience, a strong will, and confidence to reach your goal. Being relaxed and natural are the most important rules.