THAT'S ALL.
Cook pudding as package directs. Let cool, but do not allow thick skin to form. Stir frequently while cooling. Line bottom of 9 x 13-inch pan with graham crackers. Pour cooled chocolate pudding on top of crackers. Spread evenly. Put second layer of crackers on top of chocolate pudding. Pour vanilla pudding on top of this layer. Put final layer of crackers over vanilla pudding. Spread Cool Whip over top layer or crackers. (Add sprinkles, if desired.) Place in refrigerator and chill 3 to 4 hours.