We measure each item from side seam to side seam, on a flat surface. Please consider the fabric content of each item, as fabric containing stretch may give an inch or more.
Measure the fullest part of your bust and make sure the measuring tape fits comfortably.
Make sure the measuring tape fits comfortably around the narrowest part of your waist.
Place the measuring tape below your waist and above your thigh. Make sure the tape fits comfortably around your body.