At the start of the book Jason strongly recommends that you don’t use these techniques on women who are married or have boyfriends.
The reason being that it’s very powerful and there are plenty of single women out there for you to go and meet. Also if you steal a woman from another guy you never know how he might react. So you want to use this with single girls and you can do it anywhere that the two of you are alone. If it’s a girl you have met in a bar that night, you would need to isolate her somewhere reasonably quiet, and Jason talks about how to do this. The ideal situation though is probably when you’re out on a date together.