You spill a cup of coffee all over your desk. How do you react? If you're chatting on the phone with a new love interest, you shrug and chalk it up to giddy distraction. If it's right before an important meeting, you feel annoyed, even angry with yourself. Why the difference? In one scenario, it's just an accident. In the other, it goes to prove your day is doomed.

There's a reason for this: We view the world through mood-colored glasses, interpreting events according to how we feel at the time. But while we may swear that the guy who cuts us off in traffic ruined our morning, it's the way we respond that creates our experience. Life's little annoyances themselves don't sour a day; they serve as a reflection of the mood we're already in. "When you focus on negative thoughts or memories, you begin to interpret events around you through that lens, which generates more negative thoughts," says cognitive psychologist John Selby, coauthor of "Take Charge of Your Mind." It's a vicious cycle -- and one that can cause even the best of moods to plummet.

Research in cognitive psychology shows that our thoughts determine the quality of our emotions, moods, actions, and life experiences. "So nothing is more urgent or more important than learning how to take charge of our thinking," says Selby. He created a technique to break "thought addiction," or an inability to let go of past regrets and future worries in order to enjoy the present moment. The approach uses "cognitive shifting," which helps you move between states of mind and optimize your mental performance. In pairing that mental shift with specific phrases you say to yourself, you build a powerful habit that can overcome the tendency to "read" events in a negative way. In short: You stop letting little things upend entire days.

Although his sequence of exercises is deceptively simple, like any good skill, it requires practice. "You'll feel the effects right away, but if you continue to do it for two or three weeks, you will experience even more powerful results," he says. Then those flat tires, missed appointments, insensitive emails, and torn hems won't rankle you as they once did.

Wake Up
What to Do
When negative thoughts or difficult circumstances begin to upset you and make your blood pressure rise, stop and say to yourself: "I feel the air flowing in and out of my nose." Let those words gently guide your attention to the actual experience of breathing.

Why It Works
To control mood swings, says Selby, we need to sidestep the negative thoughts that generate our moods by shifting attention instead to sensory experiences. This breaks the free fall into an anxious or depressed emotional state. "This attention shift gets you out of past-future fixations and into the present moment," he explains. By practicing this first step, you'll get more adept at stopping a bad mood in its tracks.

Go Deeper
What to Do
Now that you've temporarily halted the downward spiral, expand your awareness to include the breathing experience in your torso. Say to yourself: "I'm also aware of the movements in my chest and belly." Don't make any special effort to breathe; rather, feel the natural flow of your breath as it moves in and out.

Why It Works
In this step, you add a layer to the experience. You make yourself aware of your nose and head as well as your chest and belly. How would that help a bad mood? As Selby explains, it's hard to focus on two or more sensations at the same time -- and keep thinking negative thoughts.

Open Your Heart
What to Do
Next, deepen the exercise by opening yourself up to positive feelings -- a step that goes beyond simply quelling negative thoughts. Say to yourself this third focus phrase: "I'm also aware of the feelings in my heart."

Why It Works
Mood management requires much more than mental control; it depends on creating a connection with positive emotions. In cultivating empathy through a focus on your heart, you shift from feeling bored and detached to feeling compassionate and optimistic. Selby says this expanded focus on the heart has been shown in cognitive studies to stimulate a sense of warmth and relaxation, which also helps to combat a negative mood.

Expand Your Joy
What to Do
With your heart open and your breath flowing, make a choice to fully regain your sense of well-being and empowerment. Expand your attention to include full-body awareness by saying to yourself: "I'm aware of my whole body at once, here in this present moment."

Why It Works 
On any given day, you likely feel spontaneous moments of peace that arise when you're watching children play, for instance, or exercising or witnessing a beautiful sunset. The last step of this sequence helps you consciously initiate this relaxing feeling so you feel whole and in the moment by choice rather than by chance. After all, the things you focus on help create your mood -- and what you focus on is up to you. By waking up to the present moment, you regain your sense of well-being and control. As Selby explains, "You can shift from being the victim of your mood swings to being the victor."

Text by Terri Trespicio