Think of it this way. If a deer is 30 yards away from you, you should be 12 feet above his line of sight. This will help account for sloping ground. If a deer is traveling down a steep hill, you may need to be 25 feet off the ground. Conversely, if he is traveling up a steep hill, you don't need to be as high.

If this is going to be a regular stand location for you, sight your bow for it.If you always hunt from an elevated position, set your pins accordingly.

If your 20 yard pin is set from the ground and you find yourself in a 15 foot tree, then aim 3 inches low at 20 yards and dead-on at 30 yards. At least, that's how my bow shoots.