Who wants to just ski down a hill? Thats why you build a nice big 3 1/2 foot jump to do awesome tricks off of (like a backflip). The angle and height of the jump may vary for how high you want to go and how far. A lower jump angle will give you more distance than height, and a higher jump angle will give you more height. A good mix of both height and length is a jump with a 45 degree angle. I prefer a little higher degree jump, like say 60 degrees, so it will give more height but less distance. Most jumps at ski resorts are curved to give you a kick which give you lots of height. Also if you build a jump build a nice soft landing since it hurts landing from 5ft up in the air onto solid ice. A good way to find out where you'll end up landing is to pile lots of soft fluffy snow way more than you'll need and way less than you'll need just to play it safe. Then once you know where your going to land, create an elongated and wide jump, with about half as much slope to create a nice gradual soft landing.