From experience (my spouse) in the field wearing professional attire similar to corporate world is just fine. Suit and tie, pencil skirt with blouse and proper shoes.
If you will be involved in a child care agency, for males think slacks and a button down shirt (tie optional) and some nice shoes and for women think a nice skirt and blouse or slacks and blouse with flats or heels.
Avoid overdoing the makeup and hairstyles, something professional. This is not the field to be super creative with your appearance. You can be an individual without looking like you should be in the artistic world. Nice prints and bold colors work great with browns and black jackets, slacks and skirts. Floral blouses are alright as well.
Keep accessories simple -- if you choose a "loud" piece, leave it as one. A chunky necklace to accent a simple blouse and one color skirt/pants. A brightly colored bracelet to stand against black and white clothing, with perhaps a pair of shoes (flats or heels) that match the accessory.
Avoid multiple earrings, rings and necklaces. Too much looks cheap in the industry.
I will say this, if you add bright, happy colors to your outfit you will help children and families that you work with feel very relaxed -- just use moderation.
Going pure black and white can be intimidating if not paired with something to calm the "I'm a corporate fat cat and I own your soul" look. As said, a colored necklace, shoes or bracelet can set that off. A bag of a similar color is nice as well. The less depressing color scheme, the better.... just don't turn into rainbow brite.
I hope this was of some help.