Being punny. Making puns (good and bad) and bad jokes as I go is one of the ways that I am creative every day! I just make up jokes as I talk with friends or my sisters, and as I read, even when I'm doing schoolwork. It's pretty simple: all you need is words, verbal or written, and your own sense of humor. Even if it doesn't make someone else laugh, all that matters is that it's funny to you!
Oh tiny horse, what are you doing in a store? You don't need to buy things, you're a horse.