When you first start wearing a bra; a simple training bra, or sports bra should do fine, most of these come in sizes of small, medium, and large. As your breast gets larger you will eventually need something with cups. Cups give you extra support and keep your breast in place.
1. First, make sure that you know your correct size. A proper fitting bra is important during your teen years, when your body is growing.
2. What is the reason the bra is needed; is it for support, coverage, athletics, or just for fun?

What Kind of Bra to Buy?
Training Bra- A great bra for girls who first start developing breast, or who don't fit into standard-size cups.
Sports Bra- Sports bras make good first bras, because they are flat in the cup area. Sports bras are also used to support large breasts while playing sports.
Soft-Cup Bra- The most natural-looking bra, it helps to maintain the natural shape of a girl's breast.
an extra cup size.
Push-Up Bra- A bra specially designed to make your breast appear larger, and fuller. (may lack proper support)
(Some bras have underwire, a u-shaped wire inside the fabric, which goes under the breasts and provides additional support.) (Underwire is a great choice for a girl's breasts, if she is larger than a c-cup.)

3. Shopping for the right bra
The most important thing to remember is comfort; you can use our "Fitting Guide" to help you understand what to watch for when trying on a new bra. Also keep in mind that dark colors will show through light colored clothing,and lacey bras may create bulges in areas that are unwanted.
The best thing to remember is comfort; a bra that scratchy or tight will drive you crazy by the end of the school day.

You can use our "Bra Calculator"& "Fitting Guide" at http://www.myfirstbra.us/bra_size.htm to help you with the proper fit.