Arms make the mountain begins here with the typical, nearly imperceptible, tai chi segue.  As you continue to move forward, your arms move together in a sweeping arcing motion, first forward [W= even], then rising together (10-12), until they reach your shoulder level.²  Here, your right arm is extended forward (W), very slightly bent, with your right palm facing to your left (S); your left arm is fully bent at a 90° angle (and is parallel to the floor) with your left palm (facing North with fingers pointing upward) lightly pressing against your right inner elbow. (12) [W= 70L]
     As your movement forward is concluding, your arms begin to draw away from each other, by slowly unbending your left arm and slowly bending your right arm. (14)  Your elbows begin to be drawn apart further, as your palms rotate outward (away from you) respectively and begin to rise³, your right hand moving to your right (E) and upward in an arc, and your left hand moving to your left (W) and upward in an arc. (15) 
     Simultaneous to the movement of your hands (separating and rising), raise your left toes and turn them right toward the (NW) corner by pivoting on your left heel. (15)  The conclusion of the pivot marks the conclusion of your movement in this direction (W).
     As you pivot, rotate your torso at the waist to your right, turning your whole body as one from facing West to facing North.  Lower your left toes again. [W= 80L]  Now your feet are parallel to each other and pointing to the (NW) corner.
    This is followed, in tandem, by pivoting toward your right side (13-16) on the heel only of your right foot (by first lifting your right toes), signaling the start of a shift of weight back toward the right side (E) as you rotate your waist rightward.  As both feet finish pivoting, they end up pointing to their respective corners (left, NW; right, NE) at a 90° angle to each other. [W= 70L] 
     At the same time that your feet pivot into this position, finish rotating both of your palms out away from you, so that they have reversed from initially facing each other before the descent in Needle sinking to bottom of sea (above), to facing away from each other, slightly upward, toward opposite corners (left palm, NW; right palm, NE), reaching an apex at about your eye level as Arms make the mountain concludes. True to the name, your arms here are formed as if they are sloping mountainsides. 

Fling fist  (right)    (17 through 27)
     
     Fling fist begins, here again with the typical, (did I say typical?) nearly imperceptible, tai chi segue.  Both of your arms are again drawn, first downward, in an arc toward your right side. (17)  At the same time, your torso continues to rotate rightward at the waist, turning you from facing North to facing eventually East.  As this happens, slowly raise your left toes and pivot on the heel of your left foot, pointing your toes in front of you (N), where they rest down again. (19-20)
     Just as they do, raise your right toes only (21) and pivot on your right heel as you further shift your weight to your right side [W= even], then lower your toes again, pointing your right foot due East, with your left and right foot forming a perpendicular. (24-25) [W= 70R]
     Simultaneous to this movement your hands are arcing toward the right (E), eventually moving back closer in proximity to one another as they do.  Your left elbow (first) rotates inward (19-22), moving your left forearm and hand in a slight half circle toward the East, turning your left palm from initially facing upward and away (NW) to facing forward (E). Next, your left palm moves in a large overhand arc past your left ear with the motion of your turning torso, then culminates as you fully turn your body facing East, with your left fingers at about chin level pointing to the ceiling and your left palm facing due South a comfortable distance before you. (23-26)
     Your right elbow slowly swings your right hand, first away from you to the East, (17) then directs the energy into a circle as your forearm and hand are spun around the axis of your elbow joint (18-25) until your right hand nearly circles once completely [moving first forward, as it starts to the East, then downward, backward toward you, upward, and forward again], ultimately evolving your right palm into a closed fist upon completion, hence the name, Fling fist.
     Again, both forearms/hands rotate their respective palms as your arms arc to your right.  Your left palm turns from facing upward and NW at the end of Arms make the mountain, to finishing Fling fist with your left fingers pointing to the ceiling and your left palm facing due South.  Your right palm turns from facing upward and NE, at the end of Arms make the mountain, and then follows the natural course of the circle made by your hand and forearm rotating at the elbow; it turns first to face North, then upward, before it finally closes up into a fist (22), with your right hand enclosing your four fingers, with the thumb either over them, or on the end of the fist, but not inside of your fingers.
     Your fisted right hand completes the near circle... and Fling fist... nested next to the bottom of your left palm, at about shoulder level. (26,27)  (Both arms are bent at approximately 90° angles as this posture ends.)  As mentioned at the start of Fling fist above, as you complete the rotation of your torso toward the East and fling your fist, your right foot raises onto your right heel only and pivots on the heel, redirecting the foot from pointing to the NE corner to pointing directly East.  Rest your right toes down against the floor again.  As you finish pivoting your right foot, the continued shifting of your weight rightward draws your left foot from its previous position, pointing North, until your left toes point to the corner (NE), by twisting on the ball of your left foot toward your right side.  Your right foot, pointing directly to the East, rests comfortably ahead of your left foot as Fling fist concludes. [W= 70R]

           ~   ~   ~   ~   ~

(Remember to keep your knees and elbows at least slightly bent and your pelvis tucked in throughout the set.)

(If at all possible, it is suggested that someone read the text to you - or record it on a tape and play it back - while you slowly practice the form...and slowly is the best way to practice.)

notes:

¹   Slightly touching or just very close (hovering; grazing)
                                                                                                                    _go back_

²   As you move forward, be sure that your left knee aligns above (over), but no further out than, your left toes. _go back_

³   Here your hands just begin to rise.  This movement involves rotating your elbows at the elbow joints laterally, or sideways, away from each other.  Also, your elbows do not rise above about shoulder level... no higher... nor should
your elbows ever be higher than your shoulders in Wu style Tai Chi.  The resulting compactness informed by this and other Wu style precepts is partly what distinguishes Wu style Tai Chi Chuan from its main counterpart, Yang style, which, among other things, features wider, more stretched out, movements. _go back_ 
                         
                        The links back to the above footnote numbers will only return you to
                                       the very first use of that number in the above text,
                   not to the subsequent references on this page to the same footnote number.