CHEST: Measure around the fullest part of the chest, keeping the tape parallel to the floor.

WAIST: Measure around the narrowest point, keeping the tape parallel to the floor.

HIPS: Stand with feet together and measure around the fullest point, keeping the tape parallel to the floor.

If you are in between sizes, choose the smaller size for a tighter fit and the larger size for a looser fit. If the measurements from your waist and hip suggest different sizes, you are better off going with the hip measurement. If the measurements for the chest and waist suggest different top sizes, you are better off working on the chest size.