How do you effectively control your temper when you find yourself getting angry?

I think a lot of people including myself struggle with keeping their cool. Prime example for me is when driving - I say things outloud that moments later I am ashamed to have said.

I'm trying to live a better life and be a better person. I never want to get angry and react to a situation in a way that hurts others or causes people pain. It's bad karma and not righteous behavior.

Despite that, I'm still human and make mistakes. I hope to hear some genuine responses and advice in addition to the traditional funny remarks