By talking to them. Like all relationships, communication is key.
It is a slow process, but I just try and be as natural as possible. There really isn’t anything special that I do, except understanding all the important bits of body language, eye contact, approach, posture, etc. Other than that, confidence is key. That confidence must come from the heart, not the head because they will very quickly pick up if you are even the slightest bit hesitant.
The most important thing is to know how to react when you’re in trouble and how to get out of it.
(I’ll let you know when I’ve written the book about it…)