You’re not going to be perfect, but knowing that you are looking at all information through an at least partially biased lens is the first step towards looking at the world in a more levelheaded way.
I learnt a long time ago to question every single one of my thoughts. I came to realise that they are all clouded by previous experience and most of all emotions. Once I did this, I managed to notice this absolutely everywhere.
The key is also to not let these things affect your opinion of the individual – some people may say certain things simply to provoke a reaction or cause an action, but more often than not it is simply their emotions speaking. Bias exists in all places it is what you do with it that matters.