When it comes to a savvy approach to organizing a diaper bag, it's never too early to get a head start. Case in point: Marie Clare Brush, co-founder of Oso & Me and new mom, who uses her large zip bags to pack all the essentials she needs for taking her son Lachlan on the go. Whether she's running errands or chilling at home in San Francisco, Marie Clare recommends using three playful-printed bags because they're lightweight and easy to grab versus a single, heavier tote. Aside from extra diapers and bottles, she packs what she calls her must-have, go-anywhere styles, from one-pieces and leggings to sunhats and bibs, that mix and match effortlessly on the playground, at the beach, and everywhere in between.