What you need to know for your Taijiquan practice?

1.Respect your teacher.  Place strict demand on yourself. Not respecting your teacher may not present as a problem on the surface, but in actual fact you have not realized the true essence of a martial arts principle.  If the character is not upright, attempts to take short cuts, or harbours unnatural thoughts - he/she will inevitably not attain the true essence of Taijiquan's philosophy and martial art.
Chen  Ziqiang: "Train with concentrated attention"
2. Do not be arrogant and egoistical. It is easy to attract trouble and disputes when a person is arrogant and egoistical.  Do not be arrogant with your skill, and do not be conceited in your speech.  Be calm  and harmonious in your dealings.   One who is arrogant and conceited is bound to run aground in mid-course.

3. Do not be prideful and self-satisfied when learning Taijiquan, as "an army puffed up with pride is bound to lose".   The proverb says: "Beyond the heaven there's another heaven; besides this man there's another man".   A humble man who is worthy of being taught, the venerable elder empties his treasure trove to transmit.
4.When you learn Taijiquan you should learn with concentrated attention.  Every posture must be practised and studied repeatedly.   Thinking must be natural and rational. Movements must be continuous and unbroken. If they are not continuous the energy flow will not be smooth and in order, and it would be impossible to utilise your primary dantian energy at will.
5. You must understand the way and principle of Taijiquan.  If you don't understand the way, you will not understand how to learn.  Ultimately you will not be able to experience the wondrous essence of the art.
Davidine Sim and Chen Ziqiang lecturing on Chen Taijiquan at the Warsaw Pacific and Oriental Museum
6. You must be conscientious during practice.  Understand the changes within movements.   Train with method; the method must be compatible with your body and understanding.  Train systematically; work with your concept, in order to enable your physical movements to change and alter to fit in and harmonise with your intellectual understanding.  From the first posture to the last, if you are familiar and are able to remember the principle of every direction, angle, posture and its transition, only then can you claim to have grasped a form (taolu).  This is known as "Zhao Shu" or "Familiarity with the Form".

Pay attention!
7. During practice pay attention to the functions of the movements.  Every movement has a different function but at the same time movements are mutually changeable, and supplement and balance each other.   It can therefore be said that the function of every movement in a form from the beginning to the end is elastic,  changeable  and linked.  Only in this way the power of every movement is expressed perfectly in the appropriate place.   This is known as "Dong Jin" or "Understanding Energy".

8. There must be intention during practice.  Because every move expresses its function and thought process.  A common saying states: "During training act as if there's an opponent.  In combat act as if there's no opponent".   When you reach a stage where you don't need to pause to ponder either in practice or in actual usage, when you're able to spontaneously use your every move and posture to deal with external changes.  This is the instinctive manifestation of "xin" and "yi" (mind and intent).  It is known as "Shen Ming" or "Divine Realisation".
9. Fear neither hardship nor fatigue; make unremitting efforts; in order to reach your full potential.  You must have patience, perseverance, and a calm harmonious heart in order to arrive at the final level of "Divine Realisation".