Summarize this article in one sentence.
While you want to be comfortable with the girl you like, you need to understand how far you can take your teasing. Understand that there are limits for what you can say and do to her before you make her uncomfortable and she is turned off by you completely. If you're not sure about teasing her in the first place, things such as insults about her physical appearance, her family, or her friends are definitely out of the question. Make sure the level of teasing is something she is comfortable with. You may have to test out a few things before you truly understand where the boundaries are. Trust your instincts and watch for clues about how she feels. If your flirting falls flat, make sure you don't take your bad attempt out on her. Also, if you offend her, make sure you apologize. If you have a particularly sardonic sense of humor, you may say some things that don't go over very well and it may only be a matter of time before you offend her. If you've said something out of line, give her a sincere, articulate, and specific apology. Don't try to play it off as if she is being too sensitive. If you have just met the girl, you can't tease her the same way you can a girl you've been dating for a few months. Making jokes about sex or inappropriately touching her are things you should avoid early on in a relationship. Make sure you aren't overly vulgar if that is going to make her uncomfortable. If you don't know her very well, you'll either freak her out or get a reputation as a jerk. When you tease her, don't make it feel like a personal critique of something about her or something that is important to her. If she is really into saving animals, don't try to tease her with lines like: "Wow, you have a lot of cats. Does that make you a crazy cat lady?" If her passion means a lot to her, she could take the critique too harshly and you could make her feel uncomfortable. If you disagree with something she believes, try teasing her instead with something trivial to alleviate the tension. If you disagree about politics, don't critique the way she feels. Instead of insulting her views, say something like: "While I can't fault you for your opinion here, if you tell me you like Bach instead of Beethoven, then I think the date might be over." This moves the topic to something more trivial and helps stop an argument.
Know her boundaries. Don't be proud. Don't be inappropriate. Avoid critiquing her.