All out of shortening? No problem. You can substitute oil for shortening in a cake recipe by following these tips to bake without having to run to the store.
You can substitute vegetable oil, cup for cup, for shortening. Using oil versus shortening will change the texture of baked goods. The shortening, being a solid fat, will add more air to the batter when beaten in, giving the end product more of a cakey structure rather than the more dense structure oil will give.