Look at those children. They can be happy very easily. They just need noises, papers, or simple toys.
Our adults forget about childhood too soon. That why some of us need alcohol, cigarette, or even drug to be pleasure.
Children remind us life is fun. Let smile and laugh like a child. You will be happy and make everybody happy. Remember, we don't need money, beautiful girls (boys), big houses, or nice cars in order to be happy. As one of my dear friends said "all you need is practicing".