What I've learned so far this year from getting a little bored* on groomers and skiing ungroomed snow when I can find low-angle intermediate trails to practice on:
1. Wider skis with rocker make a huge difference
2. Stance is the same, or for me,
attempts at good stance, but there's more constant effort required to maintain a forward position. Or, the varied terrain reveals my slovenly habits more clearly, so I have to focus more intentionally on staying centered.
3.
Don't try to carve. Same as
@HikenSki 's advice above: patient turns, with more attention to pivoting feet than when carving groomers.
4. Play around with naturally-forming bumps. Turn on top of them, ski in between them and use them to check speed, use them like little jumps, etc. FUN!
5. If it's really soft, get a good spring wax and a puck of Zardoz to apply at lunch.
Magic mountain is a great place to find intermediate and beginner ungroomed trails, as long as there's reasonably decent snow.
*Not bored because I'm rad, just sort of fell into a rut; wanted something more interesting.