The last two days I went skiing (well, actually snowboarding) with a friend with which I haven't before and learned some new tricks. Now 180° turns aren't a problem. First the training started with doing (trying to do) turns without jumps (this is really exhausting because a jump alleviates the whole thing - rises you in the air), then little by little I started testing steep jumps with low speed (rises you high without being fast) and it worked.
Some of the turns (when riding on the back edge of the board) can be done in an easier manner when part of it is touching the snow while turning - it looks like doing half a circle. This way if there's some unevenness it can be used to help lift the board.
The whole thing took a lot more energy than usual, because of all the jumping and falling down. Now I have muscle aches all over my body, but it was worth it.
There are no pictures because it's hard to take some with two pairs of gloves and wrist-protectors in the middle.