Our brains are wired to notice and remember the things that are wrong. It’s a survival mechanism that helped keep our cave-dwelling ancestors safe in a world where there were many physical threats. But in today’s comparatively safe world, this biological predisposition to focus on the negative contributes to stress and unhappiness.

While we can’t change our nature, we can train our brains to be more positive. This doesn’t mean putting on a smiley face and whistling a happy tune no matter what’s going on. You don’t have to ignore reality or pretend things are wonderful even when they’re not. But just as dwelling on negative things fuels unhappiness (and plays a big role in depression and anxiety), choosing to notice, appreciate, and anticipate goodness is a powerful happiness booster.

Express gratitude

Teaching yourself to become more grateful can make a huge difference in your overall happiness. The research shows that gratitude helps you experience more positive emotions, decrease depression, feel better about yourself, improve your relationships, and strengthen your immune system. A recent study revealed that gratitude even makes you smarter about how you spend your money.

There are a number of simple exercises you can practice to increase and cultivate an attitude of gratitude.

Give sincere thanks to others. When someone goes above and beyond or does something to make your day easier, be quick to verbalize your thanks and appreciation. Not only will it make the person feel good, it will give you a happiness lift, too. It’s an instant reward to see how expressing gratitude makes a positive difference in someone else’s day. It makes you realize that we’re all connected and that what you do matters.

Keep a gratitude journal. It may sound cheesy, but writing down the good things that happened to you during the day really works. Research shows that keeping a gratitude journal is a powerful technique that instantly makes you feel happier, more connected to others, and genuinely appreciative.

Count your blessings. Make it a habit to regularly reflect on the things you have to be thankful for. Bring to mind all the good people, experiences, and things in your life, both now and in the past. Focus on the blessings both big and small, from the people who love you, to the roof over your head and the food on your table. You will soon see it’s a pretty long list.

Write a letter of gratitude. Think of someone who did something that changed your life for the better who you never properly thanked. Write a thoughtful letter of gratitude expressing what the person did, how it affected you, and what it still means to you. Then deliver the letter. Positive psychology expert Martin Seligman recommends reading the letter in person for the most dramatic increase in happiness.

Find the positive in a negative event from your past. Even the most painful circumstances can teach us positive lessons. Reevaluate a negative event from your past with an eye for what you learned or how you became stronger, wiser, or more compassionate. When you can find meaning in even the bad things you’ve experienced, you will be happier and more grateful.