Making the next move

[Hardplay]

Okay so I'm a junior in high school and have been on the search lately for a girl. I'm considered to be a good looking guy who's outgoing and funny. I have recent been hanging out with a girl who

I've known for a few years. We never really had a thing but I have never been friend zoned by her either. So I was at a party with her tonight and its tough to tell if she's interested. I started off with a subtle complement and we just chilled for a while but not one on one because it was a party obviously. I honestly just don't know how to transition into flirting and letting her know I'm interested without looking timid and shy. But I also don't want to come right out and tell her because it would be weird. So please give me some very specific advice on how I should talk to her and what kinds of things to say to her when flirting. Maybe I'm actually just asking how to flirt with her as I have trouble with that anyways. Also, people always advise to me to be confident and give off the vibe that I don't need a girlfriend like playing hard to get. They say that will make the chicks want me more and be more interested. How am I supposed to get a girl that I'm interested if I ignore her? And how do I act to make her want me without making it look like I need her? How do I show her I want to be more than a friend?