Manners and politeness will never become old-fashioned.
Keep an eye on your responses. Strong responses are about you more than them.
We live in a society where mutual respect and appreciation should be considered one of the pillars of modern life.
When you get scared, embarrassed, angry, nervous, with full of emotion and bad thoughts, remember to maintain your discipline. It earns you respect the more.
It's a free world to do as you please, within the law, however it's also free to have an opinion - as well as morals, ethics and decency.
The most effective way to be self disciplined, is to submit yourself to your words.
Be sure to taste your words before you spit them out.