Happiness is contagious. Surrounding yourself with happy people builds confidence and stimulates creativity, and it’s flat-out fun. Hanging around negative people has the opposite effect—they want people to join their pity party so that they can feel better about themselves. Think of it this way: If a person were smoking, would you sit there all afternoon inhaling the second-hand smoke?

I’ve beaten this one to death over the years and can’t say enough about the importance of sleep to improving your mood, focus, and self-control. When you sleep, your brain literally recharges, removing toxic proteins that accumulate during the day as byproducts of normal neuronal activity. This ensures that you wake up alert and clear-headed. Your energy, attention, and memory are all reduced when you don’t get enough quality sleep. Happy people make sleep a priority, because it makes them feel great and they know how lousy they feel when they’re sleep deprived.

Taking time to contemplate what you’re grateful for isn’t merely the “right” thing to do. It also improves your mood, because it reduces the stress hormone cortisol by 23 percent. Research conducted at the University of California, Davis found that people who worked daily to cultivate an attitude of gratitude experienced improved mood, energy and physical well-being. It’s likely that lower levels of cortisol played a major role in this.

• Meaning. Begin with the end in the mind. Seligman recommends that we think about our own death. What do you want to accomplish before you die? What are you doing today to help achieve your long term goals? This exercise adds focus and a sense of urgency to our very short lives.
• Achievement. This is about persistence and resiliency, not simply obtaining some goal. Happy people make lots of mistakes but continue when confronted with failure and frustration.