Use a soft measuring tape. Wear light clothing and keep the tape snug but not pulling.

Top

• Chest: Measure around the fullest part of your bust, keeping the tape level under your arms and across your shoulder blades.
• Length: From the top of your shoulder straight down to where you'd like the top to fall.

Bottom

• Waist: Measure around your natural waistline, where you'd wear the bottoms. Keep one finger under the tape for comfort.
  

Choosing your size

If you're between two sizes, pick the larger one for a relaxed sleep fit. Cotton settles and softens with wear, so a comfortable, easy fit works best for nightwear.