Due to shows like "How I Met Your Mother" we hear plenty about the proverbial "wing man". A wing man is a friend of the guy looking to hook up with a girl who offers support to his friend. The wing man backs up his friend and tries to make him look more appealing (usually than he is). The female version of the wing man is a fairly new concept but should be one that the male of the species take seriously into consideration.
One strong argument for using a wing girl is the well-known fact that women tend to be attracted to men who already has a woman interested in them. It is like they think "Hmm, if she likes him he can't be all that bad." It is like women think they are ahead of the game because they interpret the wing girl's interest as having already screened the guy for suitability.
The wing girl also will help you act accordingly in front of the women. They are a woman themselves so can give you handy tips on how to attract one. The wing girl will help you be the best possible version of yourself. They will give you honest facts about how women act and think. Think of it as insider information.
Before you go out with your wing girl talk about some signals you and she can use to communicate with each other without anyone else knowing. She needs to know if you like the girl you are talking to or just want to run away screaming.
The only tricky part of the whole wing girl thing is if she suddenly finds herself attracted to you. But if you find yourself into her as well then the hunt is over.