1. It starts from the oblique position, starts from the eyebrow or eyebrow arch, extends down to the back of the nose and the tip of the nose, and then turns to the lower nasal columella, ending at the junction of the nasal columella and the upper lip, forming a smooth "S"-shaped curve. 2. From the front, the contour lines on both sides of the nose start from the eyebrow arch, along the nasal bone, nasal cartilage and the outer edge of the alar, pass through the alar groove, and stop at the junction of the alar and the upper lip, forming a smooth "S" curve;

3. The curves on both sides of the nasal ridge are connected with the contour line of the nasal tip to form a U-shaped curve with a small upward opening; The curve of the nose tip is a "seagull wing" curve with symmetrical midline.

4. Seen from the side, the "S" curve connecting forehead, nasal root, nasal dorsum, nasal tip, the junction of nasal tip and nasal columella, and the base of nasal columella fully shows the three-dimensional image of the nose.

5. At the root of the alar, we can get an "H"-shaped edge curve by dimming, and the middle horizontal line of "H" is equivalent to the position of the alar root, that is, the lowest point.