Story dice or cubes are a way to help you create stories at random. Roll a dice and whatever comes up you make up a story with that – either storytelling or written stories. As an aside, I always carry a quarter coin with me… So that when I have trouble deciding I toss the quarter and let heads or tails decide for me. Let randomness decide for you! It works very well. Story dice is just the same but with more sides than a coin.
There’s many different methods of making story dice and I thought this article by stitch/craft was the best one. It happens to be pretty old, almost 10 years old according to the article’s date. An oldie but goodie.