I'm reading a book about body language. The book has a paragraph:
The most obvious nonverbal indication of contacting is how you position yourself in relation to other people. This includes both how close you are to them and the angle at which you face them. You should always try to turn your entire body toward them while at the same time positioning yourself in front of them, judging by wherever they are facing their chest and shoulders. By placing yourself right in front of them, you can easily nonverbally contact with them , which is ideal.
I wonder if the writer wrote correctly in the expression "judging by wherever they are facing their chest and shoulders", because I think people can't face their chest and shoulders. Can you explain it for me?