1 - Decide to be happy.
Happiness is a state of mind. If you want to be happy, think happy. And yes, it's a choice -- your choice.
2 - Apply the power of positive thinking.
Being positive doesn't mean you're only counting on the good things to happen. It really means believing that no matter what happens, it is for the best.
3 - Maintain emotional wellness.
Nothing beats emotional wellness. How do you maintain it? Find time to reflect and meditate. When things get a bit overwhelming, step back, detach yourself, take a walk and see the good things in life.
4 - Have an attitude of gratitude.
When you wake up in the morning, say thanks. Be thankful for another day, another chance to make a difference. In a values enhancement camp I attended some years back, we were made to chant "Today is better than yesterday. Success!"
5 - Live in the present.
There is no point in dwelling in the past. Even if you had a sad childhood, face it, it's over. Live in the now. Today is a gift, that's why it's called present.
I remember reading a short cartoon strip of Winnie the Pooh and Piglet. Pooh asked Piglet, "What day is it?" Piglet replied, "It is today." To which Pooh remarked, "Ah, my favorite day."
6 - Love what you do and do what you love.
Find the meaning and purpose in what you do. Then you won't have reason to complain or wish you're doing something else. Life is short. Spend your time wisely. Doing what you love and loving what you do makes waking up mornings super fantastic!
7 - Approach life with humor and laughter.
Laughter is the best medicine. No, you don't need to be a clown or to act as silly as one in order to find humor in every day situations. Enjoy life! After all, it is great to be alive.
8 - Observe a healthy spirituality.
For me, it helps a lot that I have faith. For whenever I find myself lost, troubled or weary, I pray.
Have a joyful life! :-)