People who are disapointed that you don't know the band they like, wear suspenders, make ironic jokes, wear lots of hats (especially toques), read lots of books, enjoy wiriting, enjoy mixtapes, dislike most of the mainstream, or have names like Braxton would be considered hipster.
Also hipsters are often those who protest being called a hipster. It would be too mainstream for them.
your friend: "Hey, that new kid's name is Braxton."
you: "Whoa, why is he wearing suspenders?"
your friend: "I don't know, but he just asked about some band called the Hundreds. What a hipster!"
Braxton: "I'm not a hipster!!!"