I don’t know about you, but I’ve found that on many days it’s easier to smile at strangers than at the person at home. However, if you want a better marriage you need to practice certain things every day with total strangers. Imagine that in the course of one day you come across fifty people. They might include strangers you pass in a parking lot, a waitress or a bank teller. What if you looked at all of those relationships as a "pass or fail" exercise?

You pass when you smile at a stranger in the parking lot and say, "Have a nice day" or go out of your way to cheer a grumpy waitress or choose to ignore a driver who flips you off.

You fail when you come across that stranger in the parking lot and do absolutely nothing, or when that waitress has the worse day ever after her encounter with you.

Can you have fifty fails in a day and expect to go home to a successful, constructive, loving relationship with your spouse? Absolutely not. You can’t be a monster in the world and expect to be charming at home.

Several years ago, I traveled to Cleveland, Ohio, with a dear friend of mine, Kitty Victor, for a two-day seminar we were facilitating together. After landing at the airport we had about an hour to grab our bags, get to the hotel, change clothes and begin the seminar. We jumped into a cab but didn’t tell the driver we were in a hurry. However, our cabbie was driving like a maniac and his driving began to frighten us. He darted in and out of lanes, honking and yelling at the other drivers. A driver next to us was talking on his cell phone, so our driver sped up, cut in front of the other driver and slammed on his brakes—all in rush-hour traffic.

At that point I yelled, "What are you doing?" Our driver mumbled something about how he hated it when other drivers talk on the phone. I angrily quipped, "Oh, so you’re going to teach him a lesson at the expense of our safety? Quit driving like a maniac! Slow down, and get us to our hotel safely."

At that point, Kitty asked me, pass or fail?

I replied, "PASS!" Improving your relationships doesn’t mean letting people walk all over you while you bite your tongue. Unconditional love doesn’t mean unconditional abuse. Had I said nothing to the cab driver, I wouldn’t have been honoring the most important relationship I have: my relationship with myself. Physically or verbally attacking him—"You’re an idiot and the worst driver in history!"—would also be a fail.

If you want a better relationship with your spouse, you need to practice all day, every day, with total strangers. Every stranger you encounter was sent to you for a specific reason and purpose: they’re your personal home-play assignments. So, which will it be—pass or fail?

Winn Claybaugh is the author of Be Nice (Or Else!) and "one of the best motivational speakers in the country," according to CNN’s Larry King. A business owner for over 25 years with over 8,000 people in his organization, Winn is the co-owner of hair care giant Paul Mitchell’s school division. Winn is a frequent guest on national radio and a regular contributor to online publications. Visit www.BeNiceOrElse.com to sign up for his free monthly Be Nice (Or Else!) newsletter.