Whenever I want to compliment a girl I'll wait until the last possible moment and quickly look into her eyes and say something like "hey, your eyes are really pretty I must admit" and then boom I'm gone. There isn't any time for things to get awkward.
I tend to just keep the compliment to myself and if I like their eyes I just look at them more...which probably creeps them out even more than a compliment from a stranger lol
Actually, now that I think about it. I did that with a checker at Walgreens the other day. I just stared at her while accidentally dropping something.
I just have a hard time seeing myself as that creepy old man, yeah I'm 48 but I sure don't feel that age. And when I think creepy old man I always picture someone older. Shit I guess I have to come up with something different to say like, "Hey little girl want a piece of candy? I can't reach it but it's right here in my pocket"
I don't think giving compliments is sucking up especially when you'll probably never see them again. It's like commenting on a beautiful tree or sunset. Plus, it can make the person feel good.