Flirting is the way most people determine whether or not a member of the opposite sex is interested in them. Following is a quick outline on how you should go about the complex, sometimes fun, sometimes not so fun, task of flirting. It all beings with your approach.
One person approaches the other. They move into closer physical proximity. This much is clear: NO approach equals NO possibility of initiating contact. You must approach!
Example: A woman sits down next to a man in a coffee shop, or a man stands near a woman in a dance club. This is the first step. Once you approach, you begin looking for the signs.