Bras come in many sizes. You must know your breast cup size and the size of your waist. If you don't know, you can go to a professional who can measure you for the proper bra size. Your waist size will be the number, such as 36 or 38, and your cup size will be a letter, such as B or C. Together, a bra size might be a 38B or a 36C. Once you know your size, it is on to the style and fit.

You might choose a fancier style if you like, or go with a plain and simple bra. Some women prefer a lacier look. Once you choose the style and color you want, determine the fit. If there is a wire in the cup, will it be comfortable? Do you want it to make your bust look bigger? Will it give you the support you need if you play sports? You may need more than one type of bra for different occasions.

Panty size might be a little trickier. If you know your dress size, you will probably be about two-three sizes smaller in panties. Some panties come in small, medium or large, however. If that is the case, choose the same size you would as your dress size. Depending on the brand and what store your are buying from, your size may be different.

There are three basic cuts for panties: briefs, bikini and thong. Choose thongs if you wear tight pants (to avoid panty-line). Wear bikini cuts or briefs if you don't wear tight pants, or if you just don't feel comfortable in thongs. You may want to choose a style that matches the bras you have selected. Many times, bras and panties will come in sets, particularly the fancier ones.

If you don't see what you are looking for in one particular store, try another one. You might not find your size or style in every store, and that is just fine. There is a bra and panty that fits right for every woman out there. Take your time and get what works for you.