National Tell a Girl She’s Beautiful Day is pure bullshit, and don’t let anyone tell you otherwise.

[MineralMan]

182. I don't do that to strangers.

I might do a double-take and smile, and then continue on my way. I'm afraid that's a reflexive action.

I often walk in crowds. Every once in a while it happens that people make eye contact in those situation. A smile in passing is its own compliment and should never be threatening to anyone. It's an acknowledgement of another person and a smile is a gesture that says, I mean you no harm, but hello.

Compliments about appearance are for people you know, and only when the comment is positive, generally, and not some sort of sexual come-on. Compliments are polite. Sexual come-ons are generally not polite, unless the situation is an unusual one where such is expected.

If someone you see daily suddenly shows up with a drastically different hairdo, it's always OK to say, "I like your new hairdo." It's a simple compliment, shows recognition, and does no harm, unless you follow it up with some sort of noxious behavior. Compliments work best when made more or less in passing. "That sweater really complements your eyes" or "That's a great hat." are compliments. Then, you pass on or converse about other things if you know the person. It's not a sexual thing. It's just a compliment. It says, I see you and acknowledge you. That's what compliments are about.