Weight Distribution
For the most part, try to keep your weight evenly distributed between your two feet. You don’t want to put more weight on the uphill foot. Why not? The surface of the board under the leading (downhill) foot is largely what steers you. Just think of a sled going down a hill. The steering is in the front; friction on the sides of these blades will make it turn. If that analogy didn’t work for you, then consider this one: Ever do a pop-a-wheelie on your bike as a kid? What happens when you steer while your front wheel is in the air? It has no effect on your direction, right? No control. Same thing with a snowboard, if there is no pressure on the leading edge (the downhill foot), you have no steering.