Super duper unbelievably easy. Made me go well....duh, that makes sense.
A few notes....
Try and find some eye shadow with little or no shimmer/glitter in it. It'll look better-in my opinion anyway.
I have no idea what the actual ratio is, It all really depends what kind of nail polish and eye shadow you use. Trial and error...on the bright side its pretty hard to mess up.
It's probably better to use less nail polish, rather than more. The stuff I used was really cheap and otherwise crap, and also a small bottle.
Be prepared to have some extra eye shadow handy.
Find the eyeshadow you want to use, I choose this one because it had the least shimmer out of all of my spare colors, plus it was broken. Softly break it up on a clean scrap piece of paper. You don't wanna end up grinding all of it into the paper.
Grab the clear/top coat nail polish you want to use, and using the piece of paper funnel it into the bottle. Tappa-tappa, gingerly, all of that.
Shake it up! It takes a little more shaking than normal, so be patient. Now is a good time to paint a couple strokes on your nail to see what it looks like, you may want to add some more eye shadow. if it's still looking pretty opaque you can always do more coats, I did 3hree coats on my nails.
Alternatively, you can pour out some of the polish onto a piece of paper or a plastic surface or something and add the eye shadow into the puddle and stir it up that way. You can always add more eye shadow, but you can't add less nail polish