In a medium mixing bowl, combine the milk, whipped topping, and the instant pudding mix. Stir until the ingredients are well mixed, and the mixture is smooth.
In a 13x9-inch baking pan, create the first layer by placing a single layer of graham cracker squares on the bottom.
Spread half of the prepared pudding mixture over the graham cracker layer. Ensure an even distribution.
Create the next layer by adding another layer of graham cracker squares on top of the pudding mixture.
Spread the remaining half of the pudding mixture over the second layer of graham crackers.
Add a final layer of graham cracker squares on top of the pudding mixture, completing your layers.
If desired, you can frost the top and sides of the cake with additional whipped topping for a finished look.
Place the cake in the refrigerator for about 4 hours to allow it to chill and set.
Once the cake has chilled, it's ready to be served. Cut into squares, and enjoy your delightful no-bake graham cracker cake.