We've all heard the old "count to 10" advice when we're angry. In the age of Twitter, Facebook, and Social Media connectivity, it's more important than ever to teach our children about restraint. It's not like when we were kids, now, with the Internet, one bad post made in anger, or a snarky tweet made in the heat of the moment, can follow you for years.
My personal philosophy is to take a day. If in 24 hours you're still just as mad, then you can respond as necessary. If not, then you've saved yourself a big headache by acting out of anger. This is one time politics helps with parenting, because it's the same principal we use in a particularly negative campaign: Evaluate, Analyze, Plan, and Attack.
Evaluate: Make sure you know exactly what it is that has made you angry. A lot of times you'll find that you're not really mad about what you think you're mad about.
Analyze: Make sure that there was no miss-communication. One of the most negative campaigns I've ever been apart of, or even heard about, was started by a typo on a memo written by a volunteer.
Plan: Take a day (or longer) to plan out a response. I always, always, always advise starting small. As they say, you can't "put the toothpaste back in the tube", so remember to be gracious when at all possible. You can always escalate later if need be.
Attack: Attack is perhaps too strong a word, but it's accurate. What ever you have planed to do, do it and be done with it. Don't hold grudges, don't harp on the subject. When an argument is over, let it be over.