Two- manning is a tricky game, this is because it requires you and your teammate to be in tune with each other. You see, thing is, the girl he's talking to is watching the other girl and the girl you're talking to also is also watching her and the moment either of you says something dumb, it's game over for both of you. Because remember, women will always rescue eachother from weird guys and if he's weird it'll make you weird by association. So how do you assure that doesn't happen? The key to this is making it into one flirty conversation before you turn it into two separate ones. Which is how you avoid the dreaded, "I need to get back to my friend" shutdown. Here's an example of a successful two man I ran recently (it's a bit confusing but bear with me):

Other guy to girl 1: what's your name?

Me: idk man, she looks like a Chloe

Other guy: nah I'm thinking more of a Jessica

Me to girl 2: I know you're a Sarah, but what about your friend?

Girl 2: what makes you think that?

Girl 1: laughs her name's Michaela

Me: well could you tell Michaela I like her outfit?

Girl 1: yeah but she's a bit shy

Other guy to girl 1: oh, so you must be the party girl then

Girl 1: haha I am

Other guy to girl 1: well party girl, what's your name?

Girl 1: I'm Rebecca

Other guy: well nice to meet you Rebecca, I'm jack ;)

Conversation separates

Now, I'm not going to write out the whole conversation cause that's long, but the great thing about this interaction is that we managed to show which one we're interested in without actually separating them. This is good because they feel more comfortable knowing that their friend is in good hands. Comfort is important to all kinds of game but the moment there's more people involved it becomes more difficult to create that.

As always I'm open to suggestions on how I could've done this better.