Is it possible to "make" yourself happier?  Psychologist Sonja Lyubomirsky thinks so. She and her team reviewed 51 studies that tested attempts to increase happiness through different types of positive thinking. The results? There really seems to be proactive steps you can take to increase your sense of happiness.

Here are five things you can do to be happier:

Be grateful
Write a letter of gratitude to someone who has helped you in some way. This can lead to a lasting increase in happiness over weeks or even months. You don't even need to send the letter to reap the reward. Just writing it can make you feel better.

Be optimistic
Visualize your ideal future, whatever that may be. Perhaps you long to find a loving partner or secure a fulfilling and challenging job. Imagine all the details and write them in a journal.

Count your blessings
Every week, write down three good things that have happened to you. By focusing on the positive, you'll remember reasons to be happy.

Use your strengths
Identify your greatest personal strengths and then try to use them in new ways.

Commit acts of kindness
Donate your time or money to a charity and you'll not only help others, but also yourself. People who give to others report a boost in their own happiness.

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