I've found that while it's always nice to give compliments (at least, as long as you're giving it because you feel that way and not because you think you should or are trying to kiss up to someone LOL), they're better when the compliment is specific, especially if it's about a choice the person made.
Let's say you see a beautiful woman, and you tell her that. It's nice, but it doesn't really mean anything. Even saying, "You look nice today" is more specific, because it says that today there's something special about them (even though sometimes you'll get back, "What, I looked like shit the other days?"). But you can do even better.
So, let's say you tell a guy he has nice eyes. Unless he's wearing colored contacts (and you know he is), it's a nice thing to say and he should be appreciative but it's not like he had any control over his eyes and what they look like. Now, saying the tie he's wearing looks nice is better, because you're complimenting his taste. Same thing if you tell a woman that she's wearing a lovely dress, since it's something she picked out and chose to wear. You're complimenting HER, not just her body or face.
Finally, I've noticed right now with everyone wearing masks that a lot of women are really into doing incredible things with eye shadow and eye liner, since the eyes are about the only thing on their face they can show off. And, it really makes them shine when somebody notices the work they put in, the colors they picked out, things of that nature and compliments them on it. So don't be afraid to give out compliments to others; some days that can really put the pep in their step, as it were :)
