You already know about this summer's makeup essentials — and there are plenty of swimsuits and sundresses to peruse, too — but what about your mani? After all, you need to give the people something to look at while clutching your rooftop happy hour drank for the 'gram. Fret not, because ocean nails are the answer, whether you're booking it to a far away island or hopping on the Q for a sunny afternoon on Coney Island.