5 ways to think yourself well

• Positive thinking can lower stress, depression and risk of death


• Negative thoughts can be reframed into ones that are more positive


• Negativity is often rooted in fear


• Being in the present moment and expressing gratitude can boost your mood

(CNN) -- There wasn't anything that could bring singer Pharrell Williams down in his hit song "Happy." Turns out he was on to something.

Being happy and optimistic can prolong your life, help you manage stress, lower your risk of death from cardiovascular disease and even help protect you from the common cold, according to the Mayo Clinic.

Not bad at all, especially as thinking positively doesn't cost you a thing.

There's no better time to try it out than on Positive Thinking Day, which is celebrated each September 13. Here are five expert tips to help you think yourself well:

Be aware of your automatic reactions

Take a look at the following word: opportunitynowhere.

What do you see? Opportunity now here or opportunity nowhere?

"You want to understand what is your go-to, natural way of operating in the world," said Dr. Joffrey Suprina, national dean for Argosy University's College of Behavioral Sciences.

Are you the kind of person who spills your morning coffee or trips on the way to work, and suddenly the whole day is ruined? Or do you focus more on the positive aspects and the lessons that can be learned? Maybe you needed a break from caffeine or a reminder to not stare at your smartphone while walking.

Once you become aware of your tendencies, you can start changing your behavior, according to Suprina.

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Catch and reframe your thoughts

Once you catch yourself defaulting to a negative reaction, try to change your perspective and reframe your thoughts into something more positive, Suprina suggests.

A simple question to ask yourself is, "What might be some positives?"

Although it may seem clunky at first, hang in there. Suprina says that it takes about 90 days to change a habit and that celebrating baby steps and small wins is a great way to reinforce your new behavior.

It's just as important to not beat yourself up for having negative thoughts, he explains.

"Positive thinkers don't only see the positive. They realize that the negative exists but that we can choose where to focus."

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Don't believe everything your mind tells you

"It's a little-known fact that we don't always have to believe what our minds are telling us," explained Bobbi Emel, a California-based psychotherapist and coach. "We become fused with our own inner workings to the extent that they inform how we feel and act."

By observing your negative thoughts instead of judging, believing or acting on them, she says, it becomes easier to let them go.

Say to yourself, "I notice that I'm having this thought or feeling," and allow yourself to put distance between you and your reactions.

Let go of fear

"The bottom of all negativity is fear," explained Terri Cole, a licensed therapist and transformation coach in New York. "Most of the time, it is based in the future. What if this does or doesn't happen?"

The solution, she says, is to be in the present moment and identify a fearful thought as soon as you have it.

"Close your eyes; figure out where you feel that fear. Focus on that spot with your mind and breathe, and visualize the stress going away. Replace a fearful thought with a better thought," Cole suggested.

A basic meditation practice that's as short as 10 minutes a day can make a difference.

"What that will buy you is two seconds of response time," she said. "Instead of believing what your fear is telling you, you don't react."

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Find your mood changers

Sometimes life can be a little challenging; difficult news or a loss can make it hard to stay positive. In these times, Cole recommends using what she calls mood changers.

A mood changer can be as simple as having a photo of a loved one, happy experience or beautiful place on your phone so that when you see it, you'll experience a more positive emotion.

She also suggests starting each day listing three things you are grateful for and ending the day by sharing or thinking about your favorite moment from that day. Even just taking a few minutes to breathe deeply and say "I am so grateful that I'm here now" can help you improve your positivity.

"Every single person reading this article has the power to change their life -- has the power to be happy, be in love, make money. You really have to take responsibility."