Keep a gratitude journal. A growing pile of research links expressive writing with positivity and feelings of wellbeing. If the notion of journaling sounds a little too Oprah-esque, send a quick email to someone—even yourself—citing something you’re grateful for at work. The practice pays off, according to research: People who practice gratitude activities are more optimistic, feel better about their lives, exercise more and report fewer physical issues.

Cultivate a “happy habit” for at least 21 days. Find something that makes you feel great at work—whether it’s going for a quick workout or listening to Frank Ocean’s new CD while doing some filing—and work it in to your daily routine. If you can stick with it for at least 21 days, it’s more likely to become a regular habit.

Start your daily emailing with a message of appreciation. Make a point of firing off a quick message of gratitude to someone as soon as you open your inbox—and before you get bogged down with urgent requests. It can quickly become a daily habit that will boost your happiness and productivity and strengthen your social network—one of the greatest predictors of employee success at work, according to Shawn Achor, author of The Happiness Advantage.

PREVIOUSLY IN THE HAPPY OFFICE PROJECT:

• Part 1: Is a happier office really a more productive one? We’re going to find out
• Part 2: How do you improve happiness at work? Start by measuring it
• Part 3: Even happy offices still have professional boundaries…right?
• 3 things managers can do to build happiness in the workplace