What is called 'cold approach' is really all I do. I don't know anything else.
It's really not that hard as long as when you start up a conversation with a woman you don't start with the idea that anything is going to happen. You are just talking to another person, that's all... I guess the hard part, which comes with experience is just understanding body language and mannerism. You just have a gut feeling she is open to you, I can't explain it and it really isn't infallible. Some chicks might actually be attracted to you, but if she isn't available you don't have a shot. More often than not she really isn't open to you. But it's pretty fvcking obvious from the start if a chick isn't, at that point you just toss that fish back in.
The introduction is just the start of a very fast process. Success rate is very low, but you can't get ahead of yourself. I don't keep track but my guess is that less than 10% of women I approach I end up on a date with.
Any PUA that says they can teach you how to get any woman you see if a lying piece of cr@p that is just trying to get in your wallet.