Bust
Wrap the measuring tape loosely around the fullest part of your chest, at nipple level. Round to the nearest whole number. This will become your bust measurement.
Waist
Level the measuring tape around your belly button. Make sure it's not too tight and that it's straight, even at the back. Don't hold your breath while measuring. Check the number on the tape measure right after you exhale.
Hip
Hold the measuring tape parallel to the floor, Circle it around the widest part of the hips, crossing behind the back. Meet the measuring tape with your other finger to find your hip size. Hold the tape still so that it doesn't sag or twist around the hip area.