There's something about a center part that takes a look from so-so to sleek in seconds—and we're not just talking hair. This center-centric mani—designed by Casey Herman—will instantly up your cool-factor.
To get the look, start with a clear base. Then, apply two coats of Dior nail polish in "Bleuette" (similar shades at dior.com).
Next, dip a striper brush in Morgan Taylor nail polish in "Deja Blue" ($9; loxabeauty.com) and outline a half diamond on one side of the nail. Fill in the shape using the same polish and repeat on the other side, leaving a sliver of space in-between.
Clean up the edges using your striper brush, and top it all off with a swipe of clear polish. Ta-da!