So I attempted marbling today and it went TERRIBLY. Why do youtube tutorials make things seem soooo easy when they're actually really hard?! Although I suspect the nail polish I was using was the main reason it didn't turn out well. Here's a pic anyway, I gave up after 3 failed attempts.
Sorry for the flash.
I also decided to add white shatter tips to my nails and here are the results, I'm pretty happy with it.