Which is why you should only give warranted compliments.

You're right, telling someone bald that they have a great head of hair is not going to work well.

Fortunately, virtually everyone has something you can compliment them about. Even if they're a surly old frumpy shopkeeper, maybe they keep their store super clean and organized. Maybe you're impressed by their loyalty to serving the community for so many decades.

Never say anything that isn't genuine. Fortunately, most people have qualities you can be genuine about.