The subcutaneous tissue of the head is thin and blood vessels are rich, so the acupoints on the area covered with hair (except the neck) are usually needled horizontally 0.5-0.8 cun. The needles can be gently and slightly twirled and rotated. After the withdrawal of the needles, the punctured acupoints are pressed to avoid bleeding.
Baihui (GV 20)--It is needled horizontally forward or backward, or is needled to the left or to the right horizontally according to the pathological conditions.