Swing the clubhead up the slope, so it passes through the sand and into the follow-through with minimal resistance. Remember to use an aggressive swing on uphill shots, because the ball will go almost straight up and land more softly.
Uphill lies in sand give amateurs trouble because the tendency is to drive the clubhead directly into the upslope. There's no margin for error that way: If you hit behind the ball even a little too much, the clubhead will pass directly under the ball, and you'll be lucky to get it out of the sand. The key is to adjust your setup.
Rather than worry about my upper body, I focus on shifting almost all my weight to my back foot. In doing that, my upper body naturally adjusts so it's parallel to the slope. That allows me to shallow out the arc and slide the clubface under the ball.
Set the majority of your weight on your back foot (top),
let your body adjust to the slope, then swing up the hill
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