If a girl likes you and you are acting like you are not interested she will get the wrong impression that you are not into her. She will then change her mind about you and will no longer be interested.
Then you will wonder, "how come she hasn't called me in a week", "why is she giving excuses that she is busy?" etc....
She will give you another chance. Use this chance to chase her. So give her a call her talk to her.
Be nice, polite, respectful, SMILE! but at the same time act confident (she wants to look up to you, you're the man, you're the protector)
If you don't show confidence, you will look like a little boy to her and she will see you as a burden. She doesn't want to baby sit you.
TRUST ME all that "challenge" BS is high school, it will not work on real women.
NEVER WAIT a week, two weeks, to call her. She will PRETEND that she forgot about you, think that you weren't interested in her because it took too long for you to call. Don't make the girl wait. SHE IS WAITING AND HOPING for you to call. Call her immediately.
What you are trying to do is you are making her feel special, like a lady, you are showing her respect.
JUST REMEMBER that the ball is in the women's court! It is all about the female IN THE BEGINNING not you. Do not act aloof, she will find someone else. Once you have proven to her that you are "the one" she will then TURN SUBMISSIVE and WILL put you on a pedestal. Then you can finally say that you've succeeded.
DAMN I should write a book! I have to go now I'll be back later.