1-First, preheat the oven to 350°F (175°C) and grease a sheet cake pan. Gather and measure all ingredients to ensure a smooth baking process, which sets you up for success from the start.

2-Second, in a large bowl, cream the softened butter and sugar until light and fluffy, incorporating air for a tender cake that rises nicely.

3-Third, add eggs one at a time, beating well after each addition to create a smooth batter that blends everything evenly.

4-Fourth, in a separate bowl, sift together flour, baking soda, and salt. Gradually add dry ingredients to the wet mixture alternating with milk, starting and ending with dry ingredients to avoid lumps.

5-Fifth, fold in the colorful sprinkles gently to avoid bleeding colors, keeping your cake vibrant and fun.

6-Sixth, pour the batter evenly into the prepared pan and smooth the surface for even baking results.

7-Seventh, bake for 20 to 24 minutes, or until a toothpick inserted comes out clean. Rotate the pan during baking for even cooking, and adjust time if using substitutions like vegan options.

8-Final step: Allow the cake to cool completely before frosting or serving. For vegan or gluten-free versions, verify doneness by checking the center carefully. Once cooled, the cake is ready for that delicious vanilla frosting we mentioned earlier.