>>33300355 (OP)Going out of their way to create physical contact/touch
Laughing at your jokes/finding you intriguing
Lingering eyes, particularly if she's looking at your eyes deeply, forearms, ass or crotch (sometimes hands as well)
Making first moves, including initiating conversation or going out of their way just to get your attention for a moment
I always did well with girls despite being pretty quiet when I was young, these are some of the traits I picked up on when a girl started getting flirty with me.