To find your size, you need to measure your bust, your waist, and your hips.

- Bust: Measure your bust at the fullest part with your arms down by your side. If you are going to be wearing a fitted bra under your china prom dress, put on the bra before measuring. You may be anywhere from 40 inches (a size 12) to 50 inches (a size 22) to 61 inches for the bust measurement.

- Waist: Measure the smallest part of your waist, which is about 2 inches above your belly button. Similarly, this number may range from 35 inches to 45 inches or more if you are above a size 20. If your body carries most of the weight around the middle section, the waist is often the largest measurement.

- Hips: Measure your hips around the fullest part, including your rear end too. This measurement is most likely 6-10 inches more than your waist measurement.

After getting your measurements, look at a size chart online to get an idea of what size you are. Remember, most 2010 china prom dresses require some alterations to fit your body perfectly.