There is not a classier means by which to greet someone than through a hand kiss. Greeting by a handshake is too formal. A hug, too perky. And a cheek to cheek kiss? Well that can only be pulled off effectively if you are a European grandmother.
Hand kisses are universal and can be used on anyone. Whenever you perform one you will be seen as someone with class, whether it be a young child, a grandmother, a queen, or a pope. When you kiss someone in the hand it says “I don’t see you as just another person, but rather as someone that should be treated with respect”.
Adding in a french word like “madame” or “enchante” when executing a hand kiss won’t hurt either.