Three core principles...

 The Three Core Principles for Beginners of Taijiquan are: 1. loosening the arms 2. moving the waist 3. rooting into the legs. These fundamentals are essential to create correct structure, strong posture, smooth energy flow,  balanced movement and gradually  internal strength.

1. The arms are the extremities (final links) in the energy chain and must be supple, responsive, and coordinated with the body.  This can be achieved by observing the core principles 四松三随 "Four Loosenings and Three Followings":

Four loosenings - Sink the shoulders (the *Jianjing* 肩井 acupoint relaxes);  Drop the elbows (the *Quchi*曲池 acupoint retracts); Settle the wrists as if pressing on water (maintain subtle energy in the *Shenmen*神门 acupoint ); Extend the fingers (the *Laogong*劳宫 acupoint remains hollow).  

Three Followings - Arms follow the torso (waist movement drives the arms);  strength follows qi (coordinated with breath);  shape follows intention (the mind guides the motion).

2.  The Waist is the conduit of power, connecting the upper and lower body through rotational movements and driving Taijiquan’s spiralling energy.  Waist movement is distinct from hip movement.  Beginners often confuse the two, leading to excessive hip swaying.  Its essence lies in the “three axes of motion”:  

Vertical axis, the foundation of upright posture. (*Baihui* to *Huiyin* 百会-会阴 line forms the central axis);  

Horizontal axis, like a millstone turning horizontally (*Mingmen* to *Shenque* 命门-神阙 line serves as the waist-rotation axis); 

Sagittal Axis, that acts as the flexion-extension axis for forward-backward undulating motions.

3. Rooting into the legs is the foundation of Stability.  Ground the body like roots of an old tree to develop strong legs that act as the base from which all power originates. The core Principles for rooting are the 三沉四稳 "Three Sinkings and Four Stabilities":

Three Sinkings - Sink energy to the the feet  (qi to *Yongquan*涌泉), feet planted on the ground; 

Sink force to the hollows on the knees (jin spring-loaded to *weizhong*委中); 

Sink intention to the earth’s core (rooting like a tree). 

Four Stabilities - Stability when single-leg weight-bearing;  

Stability in transition between empty and solid (catlike footwork);  

Stability in rising and falling (screw-like spiral boring motions); 

Stability in explosive force (spring-loaded push off).  

These methods interlock to form Taijiquan’s energy cycle:  Loosened arms channel energy to the extremities.  A mobile waist trains multidirectional power and circulates energy through the meridians.  Stable legs generate power from the ground.