Find a pair of pants that fits well at the waist
Lay the pants flat on a smooth surface
Button and zip the pants closed
Measure straight across the waistband from one side to the other
Double that measurement to get the waist size
If measuring your body, wrap a tape measure around your natural waist
Keep the tape level and snug, but not tight
Measure at the narrowest part of your torso, usually above the belly button
Record the measurement in inches or centimeters
Compare the measurement to the pants size chart before buying