I love the classic monochrome look, and most importantly, black and white go with anything. You can use the Technic monochrome nail varnish on its own or with a background colour. I used the clear base/top coat, and then either black or white and then the monochrome varnish. You can add a top coat if you like but I felt like they would be too thick and more likely to be ruined easier.
Technic monochrome nail-varnish- Pretty little thing.com for £3. A great purchase!