play
Remember to play and have fun in nearly everything you do. There are times to be serious - when a life is on the line, when you've hurt your friend or partner, when you're at the boring end of an important project.
But most things just aren't that serious. It's okay to lose the game, it's okay to ruin the meal, it's okay to say something dumb. Just try to have fun, enjoy yourself, and play.
Most importantly - play with others, play with animals, bring them in on the fun. Play is for all of us. Life is for play.