How to Find Your Dress Size
Wrap measuring tape around your bust, your waist and your hips and write down the inches where the tape meets itself. You can use string if you don't have measuring tape.
Bust -
Measure around the fullest part of your chest.
Waist -
Measure around your waistline, usually one inch above or below your belly button / navel.
Hips- Measure around the fullest part of your hips.
Now match these numbers to the designer's size chart. Each designer's charts may differ. Size 10 for one designer, could be a 12 for another.
Note: Always go with the larger size. For example if your bust matches a size 10, but your waist matches a size 12, go with the size 12.
Alterations - For an even better fit, you can have a seamstress or tailor alter your dress. If you are between sizes, go with the larger size because it is easier to take in or tighten a dress as opposed to making it larger. | 
