First, what you're doing isn't "carving". What you're trying to do is link turns. "Carving" is when you're up on your edge during turns and leaving only a thin carved line on the snow. This doesn't mean you're doing it wrong, just means you're using the wrong term for what you're doing.
As to "ruddering", that happens when your weight is on your back leg. It's the number one problem beginners have and it's probably responsible for 90% of your problems. There are times when you do want your weight back of center, but during turns on a green run is not one of them. Your weight should be slightly forward of center so that the front half of the board is in control. There are all kinds of videos and instructions on the forum in the "Tips, Tricks & Coaching" section. Read up on proper weight distribution and edge control during turns.