The specifics for poly: A clear, fast-drying finish that, unlike polyurethane and varnish, doesn't require sanding between coats. The additives in lacquer ... finishes sit on top of the wood ...

OPI Nail Lacquer Red Nail Polish in shade Big Apple ... overtop of a white or nude base colour and sealed with a clear top coat - or with this sort of sheer, pearlescent polish.

I'll have to measure out a litre of lacquer, or clear coat as it's known as the starting amount and the three in my ratio. Then work out what volume the one part is by dividing the one litre by three.