This is a surprisingly hard technique to master. I'm gradually getting it, and I can maneuver toe or heel side as long as it's not too extreme. Here's what I have to pay attention to:
- Weight has to be 50/50 front/back foot. Not enough weight on the back and you can't get the edge to bite, and you'll spin.
- You have to exaggerate heel or toe pressure to get the edge to bite. I actually stand on my toe with my back foot when doing toeside turns.
I've found occasionally that even if I seem to be doing everything right, the back end will wash out. In those cases, I find I can regain control if I release some edge on the front foot while driving even more edge on the back.