Original pinner: Maybelline's Unstoppable Eyeliner is proof you don't need to pay a lot to get a quality eyeliner. It glides on like a liquid, but with the manageability of a pencil. And it really lasts without smudging. I like the Pewter shade.
Pick three shades in a similar color palette. The trick to making this mani modern and on point: go for three different gradations in the same spectrum—so light to dark blues or soft melons to bold pinks. This keeps the look cohesive.