When psychology professor Laurie Santos opened enrollment for her happiness course at Yale, a quarter of the student body jumped at the opportunity. It became Yale's most popular course ever. 

Yale then adapted the class for the online platform Coursera. The Science of Well Being is now available for anyone to take for free. Over 500,000 people have enrolled. The course provides an overview of happiness research, and then guides students through practical changes they can make to improve their own everyday happiness. 

Bringing in the scientific perspective 

Santos says a lot of students come to the course with misconceptions about what will make them happy. 

"The research shows that a lot of these intuitions are just dead wrong," Santos recently told Huffington Post. She coaches students to take small steps toward happiness, all based on science. 

In the HuffPo piece, Santos offers some practical advice. She says research proves that taking the following actions will increase your happiness. 

1. Strike up a conversation with a stranger.

Connecting with the people around you has been proven to boost happiness. And that doesn't mean tapping the Like button on Instagram. A real face-to-face connection -- even if it's brief -- is the way to go. Chitchat with a stranger, whether it's waiting in line at the grocery store or having a genuine interaction with the cashier. 

2. Meditate.

Have a hard time focusing because you can't stop the chatter in your head? Santos recommends meditation, which will help you calm those thoughts and stay present.

3. Reduce decision fatigue with fewer choices.

Making fewer decisions equals more happiness. Most people believe that having a lot of options will make them happier. According to Santos, science says the opposite. It's mentally exhausting to have to choose from too many options. She even recommends introducing limitations on your decision making to alleviate the burden of choosing. 

4. Do an activity for the pure joy of doing it.

Setting goals is admirable, but not if you don't actually want to achieve those goals. In fact, goal setting could make you enjoy an activity less -- especially if you'd already liked doing it just because. Try doing something or taking up a hobby without a goal in mind. Fancy that.

5. Phone a friend.

Have a few free minutes? Call a friend you haven't talked to in a while. No, don't text them. Call them. Santos says this is an easy, science-backed way to boost your mood. You'll feel more connected, even if you're far away. 

6. Jot down what you're grateful for.

Keep a daily happiness journal in which you write down three things you're grateful for. Research has shown that you're likely to see the positive effects in as little as two weeks. 

7. Get enough sleep.

You've heard it before, and Santos is going to say it again: Skimping on sleep affects your mental and physical health. Try to get to sleep at the same hour every night, and keep screens out of the bedroom. ​