I call that a sidehill lie. You can also have a sidehill lie where your feet are below the ball. I've always taken a little more club, swung easier and aimed right if it's above my feet, or aimed left if it's below my feet. If it's below your feet you gotta squat a little too. If that's not right then I've been doing wrong all this time. Of course, I am probably not the first person you want to talk to about this! haha