I'd seen these nails, like, EVERYWHERE, but I was super pissed because I couldn't recreate them for myself. Then I did a little Googling and discovered Madeline Poole, who's mushy, squirmy brain worms are all extra-creative and also geniuses. You should check her blog--she has really great stuff.
So her outline method works like a charm--a whole charm bracelet, in fact. (Note to self: Bring back charm bracelets.) I hope I did it justice.