Cushion your blows (literally)
A study from MIT, Harvard, and Yale shows that people are more flexible and accommodating when they sit on cushioned surfaces. Bruce Feiler, author of Secrets of Happy Families, suggests moving heated conversations to a sofa or chairs with padded seats.
Start your sentences with this magic word
To take an argument down a notch, start sentences with "I" not "you," suggests Linda Hill, professor of Business Administration at Harvard Business School. "This will help the other person see your perspective and understand that you're not trying to blame them for the problem," she told HBR.org.
Ask these questions
Rather than thinking about what you want to say in an argument, consider what you want to learn, suggests Hill on HBR.org. Ask "Why did that upset you?" or "How are you seeing this situation?" Once you've heard the answers, paraphrase it back to the person you're talking to show him or her you're listening.
Touch to ease tension
Putting your hand on your partner's knee or making a point to hold hands can take the sting out of a squabble and literally strengthen your connection. Touch boosts oxytocin to increase feelings of trust, and lowers cortisol to reduce stress.
Tell a joke
"Laughter releases tension and actually forces people to breathe," writes Maria Gamb on Forbes.com.