Don't be mean.
Or if you prefer a positive spin:
I have an aquaintance at work who I have told on several occasions that she is the best example of Christianity that I have ever met, seen or read about (other than Mother Teresa, but hey, who could live up to that standard?)
Why do I think that about my co-worker? Because she holds herself responsible for following the teachings of her religion. She takes the model she has been given, applies it to herself and lets the lessons learned guide her. She treats everyone she meets with respect, compassion, and (I've thought long about this word) niceness.
It doesn't matter how awful a person she has encountered. She treats them nicely. I'm sure that niceness springs from a deep love of people in general, but it manifests itself in good old fashioned respectful friendly niceness.
I once heard someone ask her how she could be so nice all the time. She just shrugged and said that it was what she expected Jesus wanted her to be.
It just seems these days that people of many religions are pointing to others, telling others to start following the teachings of whoever is in charge of their particular brand of religion, rather than letting their beliefs impact the way they themselves interact with others.
To me, if you distill all religions down to their most basic lessons, it is "don't be mean".
So be nice.