If he compliments your eyes, the color of your hair, your laugh, or an admirable aspect of your personality, then he's definitely flirting with you. He may even tease you a bit while flirting with you, like if he says something like, "That's the brightest sweater I have ever seen," but he's still flirting with you.
That depends a lot on what's comfortable for both of you. She might enjoy gentle caresses on her face and neck, or she might enjoy back rubs or having your arms around her waist. Experiment with different touches and ask what she likes or dislikes.
In his book he examines five key styles: polite, playful, sincere, and traditional. Take the quiz here to see which one you are. There is no right or wrong way to flirt, but according to author Jeffrey Hall there are five different styles.
Flirting politely involves using respectful and subtle signals to indicate romantic interest without being aggressive or inappropriate. It can include light physical contact, such as a gentle touch on the arm or shoulder, as well as maintaining eye contact and active listening.
Be impudent, a little cheeky and slightly irreverent when you're talking to her. Of course, don't go overboard with your boldness and don't start becoming arrogant. Just be playful with your words and if she finds it funny, she will definitely flirt back with you.
Beyond showing off your pearly whites, body language goes a long way when flirting. Murray suggests “leaning towards them with your body” and “having your feet face them so you are looking at them.” It's an easy way to signal openness and let the other person know you're interested.
She also might want to hug you or be open to an invitation to be hugged. The more often she touches you, the more likely it is that she is interested in you. Frequent touching can promote intimacy. When she touches you, it may mean she wants you to notice her physically.
Most women won't directly touch you to signal interest (unless you're close), so they'll test the waters indirectly by making it seem like an accident. We can truly see desire in an attracted woman's face through her lips and eyes: Her lips will slightly part.
Touching becomes flirting when it's done in a playful or affectionate manner. This could include a light touch on the arm during a joke, a playful nudge during a game, or a gentle touch on the hand while sharing a moment. The key here is that the touch is not aggressive or intrusive, but gentle and affectionate.