Here’s a quick tip to save yourself from an all-too-common social “ouch.”
Let’s say you spot a slight acquaintance at a gathering, on the street or anywhere. Naturally you say “hi.” But, ouch, he or she responds with a panicked look which probably means, “I have no idea who you are.”
You can avoid this happening by FIRST greeting them with something like, “Hi, I’m (your name,) We met at (where you met.) It’s good to see you.”
If they’re cool, they’ll pretend to remember you. But even if they don’t, they’ll have much better feelings toward you. And that’s the goal, isn’t it?