word. i look over the shoulder in the direction i spin. I spin left, so i ski switch looking over my left shoulder. Messing around on the groomers, i work to look over each shoulder evenly when turning. Turn left, look left, turning right, look right.
Practice is the only way to really dial it in. Hit up some rolling groomers and do lots of 180s over them in both directions. I can pretty much ski switch as fast as i ski forward.