How do you approach girls with a wingman?
If you're like a lot of unskilled guys, you'll both go barreling in at once, distracting and possibly intimidating the girls.
The girls are then forced to divide their attention between two guys, and you and your 'wingman' end up in a de facto competition to try to get the girls' attention onto yourselves.
For obvious reasons, this is not so effective.
Another way I've seen guys do it wrong is the one guy opens, and the other just stands out in space and never introduces himself or gets introduced.
Not much good you can do as a wing when you're never in the conversation to, you know, wing.
What we want is to get your wingman in there with you, in a way that helps you with the girl you want and (assuming her friend is cute) sets him up to succeed with her friend too.
We need a little more strategy for this than "both guys go talk at once" or "one guy talks and the other just waits, possibly forever."
Let's talk about opening things with a wingman properly.