Well if you believe those books….
Neil Strauss reckons there is a formula. His books are interesting at first, creepy after a while. The bit I remember is approach a group but ignore the lady you are interested in. It’s better of the group contains men. Make yourself the life and soul of the group but continue to ignore the lady. After a while she will become annoyed about being ignored and will interject in some way. Insult her gently, continue ignoring her. Finally start paying attention to her and slowly move all your attention to her. Bingo, according to Neil.
I would imagine for such an approach to work you’d have to be supremely confident in which case you probably don’t need any pickup technique.
I always found actually being interested in the lady you’re talking to was an excellent technique.