Sneak Peek: Meet PEOPLE's Ones to Watch 2014

Get a first look at some of the 40 up-and-coming stars we're celebrating this year – before they hit it really big

MEGHAN TRAINOR, 20

Her body anthem "All About That Bass" ruled the summer, but that doesn't mean the singer was sure she wanted to put her insecurities on display. "It was terrifying! But all the amazing support helps my confidence every day," she tells PEOPLE.