The most accurate way to measure yourself is in your underwear, keeping both feet flat on the floor.
Get someone else to measure you if possible, to ensure that the tape is straight.
Ensure that the tape is firm, not too tight or too loose.
Bust: With your arms at your sides, measure around the fullest part of the bust, keeping the tape level under your arms and across your back.
Waist: Find your natural waist by bending to one side to find the crease of your waist. At this point, measure around the waist area.
Hips: Measure around the fullest part at the top of hip, with your feet together.

WOMEN'S SIZE GUIDE