About calligraphy, what should I do if the pen is weighted in advance at the turning point?

Although I don't know what you mean by folding, I'll use horizontal folding. Every time the pen needs to change direction, it needs to go through the process of lifting, pressing and turning. You need to use your ring and middle fingers. When lifting, the ring finger cooperates to reduce the contact area between the bristles and the paper, but it does not leave contact, which can reduce the steering resistance and will not cause particularly unnatural expansion. After this step is completed, the pen tip should be close to the upper edge of the stroke, press it to the lower right corner to cover the horizontal tail, not too hard, and rely on the middle finger to cooperate. You will find that the direction of the pen has turned about 45 degrees at this time, because the whole process is interspersed with rotation. Then you can go straight down. It turned about 90 degrees at this time. It should be noted that these movements are very subtle, so micro-management should be carried out with your fingers, and don't exaggerate. Personal experience, don't copy.