Realizing she could be more grateful for her life, Gretchen challenged herself to a happiness project. She would spend a year researching what great minds throughout history — from ancient philosophers to contemporary psychologists — thought about happiness, and implement those suggestions into her life.

Gretchen Rubin had a loving husband, two daughters, a career she loved and a great New York City apartment. She knew she was pretty fortunate. But one day, riding a bus across town, she had a realization. “I had everything I could possibly want,” she thought to herself, “yet I was failing to appreciate it.” Gretchen challenged herself to a happiness project. She would spend a year researching what great minds throughout history — from ancient philosophers to contemporary psychologists — thought about happiness, and implement those suggestions into her life. Her book about that experience, The Happiness Project, became an instant bestseller. Here are the 10 key insights from Gretchen Rubin’s The Happiness Project.

  1. Make your own kind of fun. Do things because you enjoy them, not because you feel you need to.

    Trying new things is nice, but remember to be true to yourself. You can’t force yourself to love foreign films or football games and you won’t be happier if you pretend to enjoy them.

  2. Your body matters. Boost your energy — physical and mental.

    Maintaining a good sleep schedule is important, as is working out. Splurging on a fitness-related indulgence, like personal trainer sessions or swim lessons, is worth it if they’ll make exercise more fun, effective or efficient. Don’t neglect your mental energy, either; declutter your life by tackling the errands you’ve always put aside until now.

  3. Focus on relationships that matter, and start with the relationship that matters most to you.

    When choosing a relationship to focus on, pick one central to your life, like your marriage. Remember that you can’t change other people; you can only change yourself. If your partner is a perpetrator of your pet peeves, you might need to develop coping strategies rather than force him to alter his behavior.

  4. Aim higher. Don’t be afraid to fail and learn from your failures.

    We spend so much of our lives working, why not enjoy it? If you’re stuck in an industry you hate or a job with no upward potential, your Happiness Project might focus on finding a new field to pursue or position to fill. Since Gretchen already had the job she wanted, her work projects focused on professional advancement. Follow her lead and pursue a new work project, like a blog.

  5. Maintain friendships. You need to feed them with constant effort and attention.

    Friendships will die if you don’t tend to them. Remember birthdays, offer favors, avoid gossip and don’t flake on plans.

  6. Lighten up. Learn to let the little things roll off your back.

    Take fun seriously. Remember not to act as though you’re in a hurry when you’re not. Savor the unplanned opportunities for fun that crop up each day.

  7. Ponder philosophy and cultivate gratitude.

    Studies show that people who contemplate their spirituality live longer, are healthier and deal better with stress. Even if you aren’t religious, cultivate your spiritual side. Consider keeping a gratitude journal, where you write down something that makes you feel thankful each day.

  8. Pursue your passions.

    If you’ve always wanted to take up art or write a novel, do it! Set aside time for your project and do a little bit each day.

  9. Pay attention. Meditation isn’t just for monks.

    Promote mindfulness: don’t let life pass you by too quickly. Mediation is a good strategy for letting yourself slow down, but you should pursue whatever option seems most interesting to you. Yoga, breathing exercises and even art classes can all make your everyday more mindful.

  10. Money can’t buy you love, but happiness? That might work.

    You can contribute to your happiness by spending smart. Buying splurgy salads over fast food helps build your long term happiness when you feel healthier. Also, spend out: don’t save treasured purchases for a special occasion that will never come. Allow yourself to enjoy what you own.