Here is an official recipe with real instructions:
-One box of cake mix (I used pillsbury)
-One can of diet soda (I used sprite zero)
1.Preheat oven to 350 Fahrenheit
2.Mix together cake mix and soda
3.Put in greased pan
4.Place in oven for 30- 40 min until a toothpick comes out dry
5.Take out cake, cool, serve, and enjoy.