I've been practicing Yang-style Tai Chi since 1991. Lately, I've felt that even with the explosion of information available on the Internet, that there are still not enough step-by-step explanations of martial arts forms.
There are precious few books that provide detailed information about forms, with clear pictures and instructions. For those few that have clear instructions, fewer have applications, and none I've seen show alternative explanations (although I hear that Elmar Schmiesser's book on karate kata applications is a very notable exception).
Even with those qualities, better still would be a "living" document to which applications and explanations can be added and expanded over time. That is the ultimate objective of this effort.
Wikipedia has a typically comprehensive article on the history and various styles of Tai Chi.
There are as many Tai Chi forms as there are teachers. While there are many wrong ways to do a given form, there are also often many right ways that are different from each other. It's easy to get caught up in debates about what is the "best" way to do a movement. Better is to pick a style and a teacher and stick with that approach, at least for several years.
In all the movements, the body leads the arms. The arms move relatively little. They are usually in front of the body. Turn the hips and let the arms follow. Push the body forward from the heels when pressing forward, then let the arms follow in pressing forward to the target.
Move as though under water. Let the momentum of your body movements toss your arms into place. Imagine your arms as large strands of kelp flowing with the waves.
When there are techniques with an open hand, spread the fingers and thumb slightly so they are relaxed and not touching each other.
Try to let the elbows and shoulders drop. Let the head, neck and spine be vertical from the crown of the head to the tip of the coccyx. Imagine you are a marionette and the puppetteer's strings are connected to your head wrist and feet only. All other joints just fall into place.
When stepping, make sure that at all points you can stop motionless with your stepping foot above the ground. This is very different from normal, everyday walking or running where the center of gravity goes forward of the supporting foot even before the leading foot hits the ground. Until the leading foot touches the ground, it should be under your complete control. It should also be inaudible when it touches the ground, rather than landing with a sound as normal stepping does. Imagine (or even try this if you can), wearing hard-soled tap dance shoes on a tile floor. You should be able (with much practice) to step silently.
At first, it is likely that your thigh muscles will not have the strength to stay in a low stance comfortably for the entire form. If you practice the whole form several times a day, slowly, in gradually lower stances, your muscles will become much stronger. Initially, when fatigued, they may even shake. This is normal. Of course, if you have joint injuries, be careful, and do not make stances so deep they cause any sharp pain. However, barring injury, you should strive for stances that are as low as your ankle flexibility will allow. It's common to see pictures of great masters doing tai chi with high stances. It's not necessary to do low stances to do correct tai chi. But rest assured those masters did extremely low stances when they were younger, to strengthen their legs, and learn all the dynamics of a powerful form.
Let your eyes follow the hand that is doing the next technique until it hits its target. Notice how in step 8 how the eyes follow first the right hand, then the left. While the eyes may look right or left, notice how the head stays facing straight ahead, generally in line with the direction the torso is facing (play guitar is a slight exception to this however).
It is traditional (although not necessary) to face south while doing tai chi. I find it most natural to face an open area with something behind me (which is arguably a good martial application), or to face the direction of the sun.
|1. Preparation (预 备). Begin with heels together and toes apart. You should have only as much muscular tension as needed to hold any particular position. Legs should start straight but without the knees locked. To start the form, bend your knees and drop your weight while keeping the torso vertical. Step out with your left foot one shoulder width. Position the left foot so that the inside edge of your foot faces directly to the front, rather than on a diagonal as in the initial posture. Shift your weight to the left foot, then turn the right foot in so that it is also pointing forward. Then shift your weight evenly onto both feet.|
|2. Beginning (起 式). Raise arms out in front to shoulder height as you straighten your knees somewhat. Then bend elbows and drop your weight. Imagine pushing a beach ball down into the water.|
|3. Hold the ball. Shift weight onto your left foot then step out with the right. Be sure not to step out so that your feet are in one line, but rather a shoulder width apart when the posture is viewed from the front. Position your hands as if holding a beach ball, with the right hand above. The hands should be centered left to right in relation to your torso. The right hand should be level with the top of your sternum and the left hand at the level of the dan tien, just below the navel.|
|4. Ward off left. Bring your left foot up to your right, with the toe barely touching the ground. Then step out to the front, shoulder width apart and a little more than shoulder width back to front. Step out with the heel touching the ground first. Bring the left hand up to chest height, passing in front of the right hand, to end with palm facing you. At the same time the right hand travels down to end to the right and in front of your hip, with palm down. When your weight is mostly on your left foot, turn the toes of the right foot toward the front, pivoting on the heel. Twist your hips to the left to end up facing front.|
|5. Grasp swallow's tail (拦 雀 尾). Bring right foot to left, then step out with the right foot. The right palm turns up while the left palm turns down. Bring the hands to the same height with the left fingers pointing into the right palm. Shift weight onto the right foot, continuing to turn the waist to the right. Forearms continue to rotate until the right palm faces away from you, and the left hand ends palm up under the right elbow. Although the feet face to the right, the waist and torso face even farther around to the right rear.|
|6. Withdraw and press. Shift weight back onto the left foot as you drop the left hand. The right remains where it is. Turn your waist to face front as the left hand circles up to chest height. Bring the right hand back slightly towards your body to meet the left as it presses forward. Position the right hand horizontal and the left hand vertical. The hands should fit together at the heel of each palm. Press both hands forward as you shift your weight onto your right foot.|
|7. Push. Shift weight back to your left foot while bending the arms. Then shift weight onto the right foot while pushing out with the hands. Feel yourself push from the heel of your left foot, as though pushing a stalled car or some very heavy object.|
|8. Single whip (单 鞭). This is one of the most complicated moves of Tai Chi and is its most iconic posture. Shift your weight to the left foot, while straightening the wrists. Leave the right arm in place as your turn to the left. Turn the left palm up and bring the right hand into a "beak" with fingers together, wrist loose and palm facing downward. For a moment, the beak should point into the palm of the left hand. As you are shifting weight onto the left foot, turn the right foot to the front. Then shift weight to the right foot and step out with the left. The right arm gradually extends out to the right side at shoulder height, while the left palm turns outward and presses forward as you shift weight onto the left foot. As your weight shifts to the left foot, turn the right foot so that it faces nearly forward.|
|9. Play guitar. Bring the right foot in line with the left heel, facing to the front. Barely rest the right heel on the ground with the toes raised. Palms roughly face each other with the right higher than the left. Imagine squeezing an object between your forearms.|
|10. Shoulder strike. Turn to the left and withdraw the right foot. Place the left hand into the crook of the right elbow. Drop the right arm with the palm facing out to your right while stepping forward and putting weight onto the right foot.|
|11. White crane spreads wings (白 鹤 凉 翅). Turn to the left and bring the left foot in line with the right heel. Unlike the play guitar posture, this time rest the left big toe slightly on the ground, rather than the heel. The right arm raises up and pushes slightly forward, as if warding off a punch to the face, as the left hand decends to finish just diagonally left and forward of the hip, palm down.|
|12. Brush knee and twist (左 搂 膝 拗 步). The right hand drops, circling down to the waist before rising again to shoulder level while you turn to the right. At the same time, the left hand comes up to face level, as though blocking a punch to the face off to the right side. Step out with the left foot, and shift weight onto it, while the left hand continues a circle to diagonally in front of the left hip, and the right hand presses forward, palm out.|
|13. Play guitar. Shift weight back to the right foot and raise the toes of the left foot to leave it lightly resting on the heel. Bring hands, palms facing each other, into play guitar posture, as before, although this time it is a mirror image or the previous posture.|
|14. Brush knee and twist (左 搂 膝 拗 步). Repeat of step 12.|
|15. Play guitar. Repeat of step 13.|
|16. Brush knee and twist (左 搂 膝 拗 步). Repeat of step 12.|
|17. Parry and punch (进 步 搬 拦 捶). Along with single whip, this is another rather complicated movement. Shift weight back to the right foot while making a fist with the right hand and dropping it to next to the right hip. Turn the left toes out. Continue circling the right fist over to meet the left hand as you shift weight onto the left foot. The hands nearly touch, with the left palm facing to the right, and the palm of the right fist facing up. Let both hands circle to the right as you step onto the right foot, placed with the toes facing out. The hands separate once they reach the right side of the body. The right fist continues to circle down to the right hip as you step out with the left foot, toes facing straight ahead. The left hand pushes slightly back to the left side, as you punch and shift weight onto the left foot. When at the right hip, the palm of the right fist faces upward. The fist then twists to become vertical at the point of impact. Hands are roughly an inch apart at the end of the movement. Note that while many martial arts styles punch with the fist ending palm down, the tai chi punch has a vertical fist.|
|18. Push. Repeat of step 7.|
|19. False ending (如 封 似 闭). Shift weight back to the right foot and turn the left toes in and to to the front as you bend the elbows and hands come back towards the face, palms facing out. The elbows should lead the hands. The hands make a big circle out to the sides and back to the waist as you shift weight back onto the left foot and withdraw the right foot so that feet are together. The hands cross at the crook of the wrist, with the right below and outside of the left as you step out to the side with the right foot.|
|20. Closing (收 式). When learning the form, this is a good place to stop and finish the form. Make sure you can do the whole set of movements so far naturally and correctly, without thinking. Then move on to learning the rest of the form. Let the hands drop, palms down, as though pressing a ball into the water. Turn the right toes out, then shift weight to the right foot and bring the left heel, toes facing out, together with the right heel. Let the wrists straighten and hands circle down so that fingers are lightly touching the thighs.|
The next part of the form and applications, when I have time...