It has always been a gift of mine to genuinely complement since i was a little boy. If i like a haircut or the way the hair is...i naturally complement.
If i see a woman with muscular arms, you bet i mention it. She doesn't workout completely for fitness. She takes pride in her results. I'm a muscular man sometimes...but usually people ask me what kind of exercise i do. "It's all baby lifting"! It makes me feel good.
I work in a retail environment, so I meet sometimes a 100 people in any given day and I complement whenever I desire to. I've never forced a complement. I'm sure if I did, we would both know in wasn't genuine.
If you ever want to complement someone because you like something about them, then let them know. It goes a long way and it benefits both of you.
Thank you for the upvote and or reply.