From my observation, most women know how to flirt, and most men don't. I count myself in that latter group. When I was young I tried a few tactics suggested by my friends and usually ended up embarrassing myself. It sounded false and forced. I quickly gave that up and just started acting naturally. I've always been labeled, "The Strong Silent Type" which is fairly accurate. I would much rather listen than talk. And I especially don't like talking about myself. So I've never really flirted per se. Fortunately I have always gotten flirted with a lot, so almost all of my encounters have been initiated by the woman. I respond by being courteous, friendly, open, honest, and modest. I always give them my full attention and really listen to what they are saying. And if and when I do say something I always try to make her laugh. That has always been a good way to get into a women's heart. People laughing together quickly open up their souls to each other. You will quickly feel if there is a connection between the two of you.
(Having said all that, one of most straight forward flirting encounters I've had was at a classy restaurant outdoors on a warm summer evening in a high-end resort. I was dining alone and two attractive women who had been dining nearby were leaving their table. As they walked by my table, one of them picked up my folded napkin and blew into it so it was tented up and set the tented napkin back on my table. She then whispered, "That's a blow job to go." She gave me their room number, told me to stop by after dinner, and walked off. I never said a word. Needless to say, I did stop by their room latter and enjoyed a wonderful evening with the both of them.)