Master Chen Zhonghua Online Lesson on May 4, 2021 - Kelvin Ho
Lock the right elbow-shoulder-kua triangle, but place it horizontally.
Rotate to the right horizontally using the kuas.
First make the line between the right elbow and left foot. The left foot is supported by the floor.
Later make the line between the right elbow and left knee, but we need to keep the knee up (i.e. the left knee cannot point to the floor).
As we rotate to the right, the right elbow and left knee must continue to expan
Source: https://practicalmethod.com/?p=75585