In the same way that every girl should have a capsule wardrobe of versatile classics that can be worn throughout the year, every girl should also have a collection of basic nail polishes for different occassions. Not everyone needs a fridge full of bottles like me (66 of them, to be exact) because a well-edited set of essential colours in good quality formulas will cover all the bases. This means that you can accessorise your more expensive “investment pieces” with cheap polishes in trendy shades when you want to mix things up. Here is my pick of the five best…