In this nice cartoon, Sarah Glidden looks at all the ways that people in different cultures greet each other, from the handshake to the hug to the kiss on the cheek or to the kisses on both cheeks to the namaste sign and so on, and the awkwardness that can arise when one person expects one thing and the other expects something else.
Navigating this is not easy. I myself tend to take the coward’s way out, especially when it comes to more intimate greetings like hugs and kisses, waiting until the other person makes the first move before responding similarly. By just smiling and slightly bowing or nodding my head until it is clear what is called for, I manage to avoid committing a faux pas. If the other person is similarly conflicted, then the smile and the bow/nod becomes the greeting.
But that does not solve all the problems. I recall one awkward occasion when after a long time I met a colleague with whom I am friendly. As she came close, she smiled warmly and her arms went up in what I took to be a pre-hug motion so I too went in for the hug. At the last minute I realized that what she had been intending to do was to adjust my jacket collar that had been partially turned inside. I was mortified for misconstruing her action but it was too late to back out so I hugged her anyway and she hugged me back. Embarrassing!
Even since then, though, she hugs me whenever we meet so I figure that she was not offended.