Do:<ul><li>Check-in regularly with good friends (around 2 weeks for very close friends).</li><li>Celebrate the good things in their life; let them know through active and constructive listening. </li><li>Studies show people love hearing themselves talk and talking about themselves, so let them.</li></ul>

Be Proactive About Your Relationships

Experiences trump material purchases (in general) for the 5 following reasons:<ol><li>Experiences improve over time while physical items can get old quickly.</li><li>People revisit experiences more often </li><li>Experiences are more unique and can simply be enjoyed.</li><li>We adapt slowly to experiences because it takes our brain longer to get used to them while we are better able to adjust to material purchases.</li><li>Experiences are social.</li></ol>

Spend Money on Experiences

"When people realise that their life is almost over and look back clearly on it, it is easy to see how many dreams have gone unfulfilled. Most people had not honoured even a half of their dreams and had to die knowing that it was due to choices they had made, or not made. Health brings a freedom very few realise, until they no longer have it."  - A study on the Top 5 Regrets of the Dying

Don’t Let Time Slip Away

Researchers found that setting ambitious goals tends to make people happier. Big goals are often an important element of getting people moving in the first place.

Aim High

Research has found that exercise is a proven strategy for feeling better, increasing your energy levels and reducing tension.The release of endorphins has an addictive effect, and more exercise is needed to achieve the same level of euphoria over time.

Exercise

Research shows that feeling “rushed” is a one-way street to stress and unhappiness. Too much boredom can be burdensome. To find a balance, learn to say "no" to opportunities that do not excite you.

Be Busy, but Not Rushed

Humility is not thinking less of yourself, but thinking of yourself less.  - CS LewisSelf-esteem that is bound to external success can lead to small spurts of happiness but is not long lasting. Focus more on the betterment of yourself for the sake of those around you, rather than for your own ego.

Think of Yourself Less

Great minds discuss ideas; average minds discuss events; small minds discuss people. - Eleanor RooseveltDeep conversations are often those we reserve for close friends and family, which explains why close relationships are so important for our happiness.

Move Beyond the Small Talk

Small pleasures matter. Research has shown that you need to have small wins along the way in order to be truly happy.

Treat Yourself 

Researchers found that although the process of becoming proficient at something took its toll on people in the form of stress, participants reported that these same activities made them feel happy and satisfied when they looked back on their day as a whole.

Pick a Skill; Master It

According to research, showing gratitude boosted happiness by a noticeable level.Writing thank-you notes, or just a nice letter, is an effective method of increasing happiness and life satisfaction.

Show Some Appreciation

Research suggests that the best way to predict how much we will enjoy an experience is to see how much someone else enjoyed it.

Observe Happiness in Others

While happiness is defined by the individual, I've always felt it foolish to declare that nothing can be learned from observing the happiness of others. Examining how to be happy is benefited from observing the patterns of others, and then taking only what you find useful.