One really easy way to figure out the motions for nose blocks is to put on your skis in your living room, on a carpeted surface. Do a superman leap forward, and stop yourself from hitting the floor with your hand. Now do it again, but a little less exaggerated. Keep doing this until you've mastered the motion of standing up to your tips.
Now take it to the snow- roll up to a transition, slowishly, and pop up and forward the same way. Just try to balance the first few times, don't go for the grab until you've got the balance down.