Follow these steps to create your amazing Football Field Cake:

1. Preheat Your Oven: Begin by preheating your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

2. Mix Dry Ingredients: In a large bowl, sift together the flour, granulated sugar, cocoa powder, baking powder, and salt.

3. Combine Wet Ingredients: In another bowl, whisk together the milk, vegetable oil, eggs, and vanilla extract until well combined.

4. Combine Mixtures: Gradually add the wet ingredients to the dry ingredients, stirring until the batter is smooth and lump-free.

5. Divide Batter: Pour the batter evenly into the prepared cake pans.

6. Bake: Place in the preheated oven and bake for 30-35 minutes. A toothpick inserted in the center should come out clean.

7. Cool: Remove from the oven and allow the cakes to cool in their pans for 10 minutes. Then, transfer them to wire racks to cool completely.

8. Prepare the Icing: While the cakes are cooling, mix your buttercream frosting with green food coloring until you reach your desired shade.

9. Assemble the Cake: Once the cakes are completely cool, place one layer on a serving platter. Spread a layer of green buttercream frosting on top.

10. Add Second Layer: Place the second cake layer on top of the frosted first layer and frost the entire cake with the remaining green buttercream.

11. Create the Field Lines: Roll out white fondant and cut it into strips to create yard lines on your cake. Apply these lines to the cake using a small amount of frosting to help them stick.

12. Add Decorations: Use edible gold or silver balls to represent spectators in the stands or add other fun decorations as desired.

13. Top with a Football: If using, place a football cake topper on the center of the cake for the final touch.

14. Chill: Refrigerate the cake for about 30 minutes to set the frosting before serving.

By following these steps, you will have created an incredible Football Field Cake that looks as good as it tastes.