Then mix the wet ingredients. You get the idea ;)  

I always wind up with little helpers in the kitchen. As long as they don't all want to help at once, I'm good. 

Of course, having little helpers also means these little messes happen. Hazard of the occupation ;) 

After mixing the wet ingredients, you guessed it, you add the dry ingredients. The only variation I make to this recipe is by adding a teaspoon of cinnamon to the batter in addition to the cinnamon in the streusel that the recipe calls for. More cinnamon = Happiness. Unless of course you misread the instructions and put a tablespoon instead of a teaspoon. Ask me how I know. 

Layers of batter and cinnamon sugar yumminess! Then you just pour melted butter over the top and pop it in the oven! See, super simple!