I know, this will come as a shock to some of you (my husband included) but I don't have the greatest "inside voice." Somewhere and somehow, I convinced myself, that if you talked at a normal octave about the person right next to you they wouldn't suspect you were talking about them. I mean, who talks about someone while they are sitting right next to you? I know, this sounds like a ridiculous statement, but the key is to not point, not look in their direction and not lower your voice. Any of these missteps can instantly turn a nice dinner observation or a friendly talk with a friend into a rather nasty situation.
Might I also add that when you talk about someone keep them at least in your peripheral vision. Turning your back or a quick corner can lead to a disastrous outcome. For example, today a customer of mine decided to bring over his check to me while I was putting in an order at the computer. For some reason, he decided, as he dropped the check next to me, to make a loud kissing noise in my ear. Immediately, I thought it was one of my co-workers messing around and I said, "Thanks doll." However, as I turned around to see my co-worker, all I saw was a strange looking Asian man sipping his coffee. Now, I'll admit I was slightly rattled from his "sign of affection?" but that is no excuse for breaking one of my cardinal rules. After about ten seconds of thinking about his ridiculous smacking lips, I said out loud to my co-worker, "The strangest thing just happened to me. Some idiot brought over his check and made this disgusting kissing noise in my ear." And then the mistake. My co-worker asked, "Which one?" and I said, while turning, "He's this creepy Asian..." and there he was...right behind me.
So remember friends: act natural, keep them always in your sights, don't point and judge away.