Using a soft measuring tape, start with with your feet shoulder-width apart. If available, use a mirror to ensure the tape stays parallel with the floor from front to back.

Bust: Measure under your arms and around the fullest part of your bust. If you intend on wearing a bra with your garment, measure with a bra on. If you plan on going braless, measure without a bra.

Waist: Measure at the smallest part of your torso. Another way to measure your waist is to bend to one side and measure where your body folds. Tape should feel snug and comfortable but not pulling or falling down. 

Full Hip: Measure at the fullest point of your hips including your seat.