Check the eyes and smile. The pupil of the eye will dilate (grow large) if they are deceiving you and lying. Can they look you in the eyes? And check to see if the smile appears forced or fake. A mouth with clearly defined lips, the outline appears to have been etched with a fine pen. Also, if there is a perfectly straight line where the top and lower lips meet you will find a sincere a friend as you can hope to have.
If any of you have any questions, that are on your mind, let me know. We can share information here.