There’s one simple trick I was taught several years ago, to help a client feel at ease. We all know that portrait subjects can sometimes get nervous or overthink their appearance.
Every photographer has a primary eye — left or right — that they typically look into the viewfinder with. If you use your right eye in the viewfinder, you can keep your left eye open. If you use your left eye, you can look at your subject before you click the shutter button, and immediately afterward. Regardless, the most important thing is to SMILE! By smiling and keeping eye contact with the subject, the intensity and anxiety that the lens often causes can be diminished.