If a girl is by herself, approaching and starting a conversation is straightforward. If there are three girls, starting a conversation with one isn't too hard since the other two can chat with each other. When it's just two girls, though, I've been having difficulty.

Should I just ignore the friend, or include the friend in the conversation while blatantly escalating with the girl I'm interested in, or what?

I realize having a wingman would make this a piece of cake, but I'd like advice for when I don't have a good wingman handy.