OK.. so this is far from perfect. Mainly because the red polish I chose was far too thick and didn't work very well, but I tried. I also chose to use colours different from the actual YSL Couture promo pic. Im sure that with a bit of practice though I could nail this look, so to speak ha.
Im not sure if anybody would be interested, but I'd be willing to write a guide showing how I achieved this look. Just pop me a comment if you think a guide would be helpful.