Riding switch, you want to have a little pressure on the shins; it makes it easier to maneuver the skis under your body since when you turn, you're going to be staggering your feet in the direction of your turn.
Spotting switch is a little tricky. First learn by just keeping your eyes on the landing of the feature. once you lock in on it, look straight uphill as you land. if you look at your feet, you will land hunched over and may fall. Once you get that dialed, you can start landing while looking at the next feature.
Taking off switch is really easy. All you have to do is just stay balanced over both feet with even weight and be patient. if you pop too early, you will catch the tip of your trailing ski. Also like mentioned above, stagger your feet in the direction of your spin. For example, spinning left, drop your left foot behind you as you approach the jump and look over your left shoulder.
Hope this helps =]
the best thing about skiing backwards is you can see where you've been.