Even though we typically practice our golf shots from flat surfaces and lies, it is actually quite rare to have a completely flat hitting area on the golf course. There is almost always some sort of slope in the fairways and rough. Hitting from these sloped lies can be very difficult but there are several keys to each type of slope that can make it much easier to make contact and hit the ball where you want to.
Ball below feet: When faced with a sloped lie where the ball is below your feet, the ball will be further
away than on a flat lie. To get closer to the ball bend your knees and sit down into your stance as if you were sitting in a chair and choke up on the club to the butt end of the grip. Aim left of the target , the slope of the ground and the angle of the club face will force the ball right. The more severe the slope the further you should aim left. During the swing, resist standing up and out of your “seated” stance and keep your weight towards your heels.
Ball above feet: In a situation where there is a slope that causes the ball to be above your feet, the ball is closer to you than a typical shot. To prepare for this; take a stance where you are standing up straighter than on a flat lie with your weight towards your toes. Choke down on the grip; on a severe slope “club up”, gripping down low on the club will not allow a shot to go its full potential distance. You will need to use a flatter swing plane (like a baseball swing) to make better contact and avoid a “chunk”. Also, aim right of your target as the slope and the angle of the face will force the ball left.
Downhill lie: Any shot in which your feet are not level will complicate the stroke, when hitting from a downhill sloping lie. To overcome this set up to the ball with a wide stance for balance, the weight of your body will naturally be toward the front foot. Match the angle of your shoulders to the slope of the ground and put the ball back in your stance, this will minimize the tendency to chunk the ball. The slope will cause the ball to come out on a low trajectory, it is a good idea to club down in these circumstances, to manage the added distance and rollout. During setup there is also a need to aim left of your target; the slope promotes a swing path resulting in a fade and the ball position and setup promotes a bit of an open face at impact. Finally, make a steep attack on the ball to avoid chunking and to get the ball on a higher trajectory. 
Uphill lie: Just like the downhill lie, widen your stance and match your shoulders parallel to the slope of the ground. The ball needs to be forward in the stance to prevent thin contact. The ball is going to come out with a much higher trajectory than a shot from a flat lie so you will need to “club up” to hit the ball the desired distance. The slope promotes a swing path that is consistent with a draw and the clubface is likely to close before contact, it is beneficial to aim right with this lie. During the stroke you will actually want to swing up the slope to contact the ball. A steep stroke in these instances usually causes fat contact.
