How does flirting naturally look?

Usually it starts with eye contact. You try to maintain eye contact with the person you like and smile, to let them know that you are interested. They are expexted to do the same. They you walk up to them, or you watch them approach you (which I think is way harder) and you start talking. A conversation is best to be started by saying hi. (if you were more specific about yourself I would have gave you more specific advice) Then you talk and bla bla bla. Then comes the touch. If you want to touch the person you are interested you should do it on the shoulder. That basically means "hey I like you,(in a non agresive sense) and I hope you like me". And the final stage would be kissing but that not really flirting, and you should not do it during your first conversation.

But if you asked this because someone talked (or called you names and smiled) to you and you want to know if they like you, know that there are many other things involved, like body language and such. Some people do things that they consider to be flirting, while others don't., and some people are shy and they cover it up with mild hostility.