You gotta get off green circles on a fresh snow/powder day... The snow slows you down, so gotta hit steeper runs to keep the same speed as you would on a groomer day. Open it up and have fun. Falling doesn't hurt, and there's no ice to slip on.
As others have said, put most of your weight on your back foot. If you've ever wakeboarded, that's more the stance you want in powder. I love powder days cause I go way bigger of jumps than I usually would. Soft landings are great!