I'm not sure you can. Chances are, you're not a professional acrobat, and won't have the mental discipline to correctly twist your body in midair. Doesn't hurt to try to do what the above poster recommended, though.
fall like a long wood plank stood up tall that got blow over by the breeze. Landing flat like a face plant will be a much more fatal way to land than if you jump regular and if you try to nose dive you most likely will end up going feet first because of survival. You probably will end up going feet first no matter what because of survival instinct unless you are clutch. Another option is to hang by your feet and than drop or push off away from the structure with your hands and feet. You could also ride a balloon to a high height and then hang and fall. Maybe you could time it so you fall once you fall unconscious from the lack of oxygen in the upper atmosphere.