When a male spots a female that he finds attractive, he may look for clues that the female is interested in meeting him. If he does not receive any cues from her, he moves on to the next attractive female. To prevent a potential mate from moving on, the female needs to know how to flirt and send cues to let the male know that it's OK to approach her.
The first thing you need to pay attention to when flirting with a man is your appearance. If you don't dress in such a way that encourages a man to notice you, you will not have much of a chance to apply your flirting tips. The men in the vicinity will be focused on other women who dress in a flirty fashion. The idea is for you to wear clothes that show off your figure, but not clothes that are so tight that you bulge out of them.
Don't be shy about sending cues to a man you find intriguing. You won't be seen as desperate or trying too hard. At the end of the day, the guy will think that it was his brilliant idea to approach you, rather than the fact that it was you casting your line and reeling him in with your flirting. When you are in the man's presence, smile at him so that he can notice. Then look away. You can repeat this move a few times, so that he doesn't think his mind is playing tricks on him. By the time you are done, he should know that you are interested in meeting him. If he is single and also interested, he will make his way over to you. While he introduces himself, keep smiling to let him know you that is a pleasure for you to have made his acquaintance.
Show that you are open by fully facing the man. Pay attention to what he is saying, and keep your arms open in a relaxed and inviting position. Folded arms signal that you are closed off to his advances and that he may have made a mistake in approaching you. Lean forward or sit closely to him to indicate that you are attracted to him. Nod and look him in the eye to let him know that you are into whatever it is he is saying. You can touch him to signal this, too. Unless he is married, he shouldn't mind your accidentally touching his arm of brushing an imaginary piece of lint from his clothing.