I've found that if the person I'm talking to is pretty outgoing and extroverted they try to steer the conversations we have into topics about me and introverted people tend to avoid personal topics. Most people want to make plans to see you again if they like you though it may not necessarily mean they're interested in you sexually.
I'm pretty shy when it comes to guys I like, so I kinda tiptoe around them and tend to not say much around them or avoid eye contact because I'm like a deer in the headlights when I make eye contact. But generally, if I've known this person for a few months, I try and shake off the insecurities and gradually accept that I'm not always going to say something stupid and it's all good.
From my experience, girls like to get close if they're interested in you, lean towards you in conversations, touch your body, always playing with something in their hands, regardless if they're extroverted or introverted. It's like an uncontrollable reflex lol