I didn't really go into this with a clear plan, and I'm not entirely sure I like what resulted. Nonetheless, here are my toes at the moment:
The base colour is Love&Beauty - Light Grey/Multi. This is a really sheer grey polish with this kinda flecky blue shimmer in there. Here's a picture of just that (I think I ended up with four coats for the final, and this is two):
Then I added some kind of snowflake/flower contraption with a white Migi Nail Art Pen. Then I hand placed a little bit of black glitter.
Yup. It's very subtle compared to what I had before. It probably won't last long. xP But I definitely do like that base colour, so I'll have to see what else I can do with it. :)