"Be kind, for everyone you meet is fighting a hard battle." --Ian Maclaren, Scottish author and theologian

Last week was a tough one for me as a leader.

One of my companies had an extremely toxic employee I had to let go on Friday. And throughout the week, I was traveling a lot from New York: to Portland, Maine on Monday, Boston on Wednesday, and Washington D.C on Thursday.

By mid-day Thursday, I was physically and emotionally exhausted. I was hungry so when I had a little extra time before my afternoon meeting in Washington, I looked up the best sushi place in town on Yelp, and walked nearly a mile to get there. I arrived only to find a sign that said: "Closed this week for renovations."

A Tough Week, a Chance Encounter

At this point, I lost control of my emotions, and shed some tears. I was so tired, so hungry, and so stressed. Determined not to be defeated, I began walking towards my next meeting, on the lookout for a place to get something to eat on the way. A beggar on the street interrupted my walk, asking, "May I have a quarter to get something to eat?"

Typically, I don't stop for beggars. I prefer to give charity through organizations that distribute food and shelter. But this time, for some reason, I stopped, and searched my pants for some change. I couldn't find any, so I decided to reach for my wallet to grab a dollar instead.

"I swear, I don't drink or get high, sir, " said the man, perhaps sensing that he was going to get more than change. "I could really just use a dollar to get a sandwich."

I didn't have any one dollar bills in my wallet, and this point, I didn't want to stiff the guy, so I took out a $20 bill, and handed it to the man.

"Oh, Jesus," he exclaimed. "God bless you! Thank you so much, sir!" he said, and I went on my way.

Instantly Feel Better

I couldn't believe how much better I felt. I had gone from feeling depressed and exhausted, overwhelmed and stressed out, to feeling blessed, fortunate, happy, and high on life in a matter of seconds and at a remarkable cost of just $20. What some would argue was a selfless act, I might argue was selfish, in how great it made me feel.

A random act of kindness is the secret to instantly improving your mood any time you want. 

You don't have to give $20 to a man on the street to feel better. You can pick up litter. You can call your grandma. You can hold the door for the next 10 people to come and go from your office building. You can retweet a bunch of random people.

You can do anything that takes you out of yourself and if, only for a moment, focuses your time and attention on someone else, needier than you. 

Kindness Makes You a Better Leader

This is at once a selfless act and a selfish one, because no matter what, you'll feel better after being kind. Then you'll be more prepared to be the leader you are, and take on the world and its challenges.

By the way, I went on to have two very productive meetings in Washington that afternoon, and then returned home feeling refreshed and re-committed to leading two companies.

How do you inspire yourself when you're feeling down? Tell me in the comments below. Here are seven other ways I do.