Get out there and flirt!

Give out the right signals
Be sure, and this is very important, that you give out the right signals. If you are interested in someone enough to want to take it further than just flirting then flirt like mad. However if you are flirting just for the fun of it (and there is nothing wrong with this, most women flirt just for fun) make sure that any man you flirt with knows this, and that your body language isn't telling him otherwise. Also some men, in fact most men, can be a bit on the slow side when it comes to sensing what a women wants, which may mean you might have to spell it out for him.

Dress for the eye
If you want someone to approach you it is much easier if you're wearing a conversation starter (i.e. a badge, a crazy wig.) This will also show that you have a funny side. If you are trying to attract the attention of the office hunk wear a bit more make-up and a skirt that reveals a little bit of leg, (but not short enough to show your undies.)

Feel good about yourself
A positive outlook is contagious. Feel good about yourself, about what you wear, about your hair and others will feel good about you.

Get eye contact
Some people might take offence if you stare at them for a long period of time. Let the guy know you are trying to catch his eye then when you hold his gaze give a gentle smile and let your eyes drop to the floor. He won't feel intimidated and he will know that you are interested.

Smile
This shows friendliness and self-confidence, which is viewed as one of the most attractive qualities a member of the opposite sex can have.

Who's watching
Walk though a group of men and have your friends watch to see who is checking you out.

Mingle
Walk about and mingle with people. Get to know friends of the guy you are trying to attract. You could even ask them a question or two about the guy. (But don't over do it, you don't want to sound desperate or too keen.)

Separate yourself from friends
Take time out to be alone for a bit. This will make you more approachable. Men some times feel awkward approaching a woman when she is in a crowd of other women in case of rejection.

Be polite
If you aren't interested in a guy, be polite when you reject him. It takes a lot of courage to approach someone so be sure you turn him down in a way that you would appreciate being turned down.

Have a conversation starter ready
It is no good approaching a man if you don't know what you are going to start the conversation off with. You could start with a witty line such as "great tie may I buy it from you when you are finished with it?" Or you could simply start with your name, but remember to back it up. He might be just as nervous as you.

Boost his ego
A little flattery never hurt any body. Men have always used flattery on women to get what they want so why can't women? This is one of the best ways of flirting. Boost his ego and you will have him drinking champagne from your stilettos. (Yes please!). If he has gorgeous eyes, a great head of hair, is well groomed, tell him. We all like to be complimented. Flattery gets you everywhere.

Be interested
Ask him lots of open-ended questions. Ask him his interests, what he does for a living (but make sure he doesn't think you are only interested in how much he earns). You may find that you have a lot in common other then physical attraction.

Make the first move
A lot of men find it attractive when a woman approaches them and find it easier and more relaxing to talk openly.

Don't pretend
Don't pretend to be something you are not, especially if you would like to see the guy again. Don't lie about your age, don't avoid telling him you have kids or even that you wear a wig. When he finds out the truth he may decide that he doesn't want to take things any further because of a lack of trust.

And finally
Only give out your real phone number if you decide to take things further.