They shape our identity in every way possible. First of all, genetics physically shapes our identity. We wouldn't be who we are if we didn't have our unique set of genes. Secondly, history shapes our culture, and culture is one topic that includes tradition and religion. Moreover, our culture shapes the society we live in. So you can sort of tie all of those together in whatever it is that you're writing.
As far as history goes, we would be nothing without our history. For example, as kids, we do stupid things, make mistakes, and learn from them. This is all a part of our history. If some kid hadn't broken their arm in the second grade from falling off of their bike trying to jump a ditch, then they wouldn't have learned that they can't be reckless without consequence.
Traditions are something that we all have in our lives. Whether it's a morning ritual or Thanksgiving, these are all traditions that shape our being.
Religion is fairly straight forward - if you believe in something then that becomes a part of your identity. If you change your every day actions because of your religion, whatever that may be, then religion is shaping your identity.
Society affects everyone. We are all affected by material things that society has told us are cool.
I hope this gives you something to get started with.
