(DISCLAIMER: I am not a qualified instructor. Seek professional advice if you think I am talking shit)
Obviously the first step is to get your groms accustomed to side-slipping and working out where their edges are, but I found that the lightbulb moment only really came once they were comfortable with speed.
As such, from pretty much day 2 or 3 onwards, we started straight-lining greens and shallow blues (with me riding behind/in parallel, holding onto the back of their coats in case they caught an edge), rather than trying to execute perfect turns at low speed.
The holding-the-back-of-the-coat technique (patent pending) allowed me to initiate shallow turns and get them used to the sensation of carving – and I found that if anything went wrong, I was able to stop them falling.
Importantly, it also kept me out of their line of sight, so they were focusing on the hill (not me), and also allowed me to let go without them realising – so from early on I knew they were capable of riding solo, even if they didn’t know that was the case.
As per section 4, it is super physical (particularly tough on your lower back) but I found it to be the most effective technique to building their confidence and independence.