Flirting

How many of us do it, flirt, that is?
I am just a naturally friendly person. In my coffeeshop job I am paid to be friendly and outgoing. I am paid to take an interest in you and have you leave the shop feeling good. I am so good at it I am not aware anymore that I am friendly.
However I have been called the biggest flirt in our shop. I guess it comes so naturally to me I don't know I am being flirty.
Herein lies the problem.
I don't consider my behavior flirting. But my co-workers just look at me and say "there she goes again! ". "Can you teach me how to flirt" . "How does she know all those people"?
How do you know someone is flirting??
Guys and girls, how do you know? Do you find yourself flirting often? With whom?
Let's compare our flirting techiques
Coco