For men, as a general rule, the number of inches measured will equal your size, when measured correctly. Be sure to measure your body. Do not measure over shirts or slacks.
Neck: Measure around base of neck (lowest part). Number of inches equals neck size.
Sleeve Length: Start from the center of the back of the neck and measure across the shoulder to the elbow and down to the wrist.
Chest: With arms at sides, measure across fullest part of chest, under arms and across shoulder blades. Keep tape measure straight across back.
Waist: Measure your natural waist at the height you normally wear your pants. Keep tape measure firm but not tight.
Inseam: Measure inside of leg from crotch down to top of shoe. Or measure a similar style of pants that fit well. Measure from the crotch seam to the hem.
Be sure to measure your body. Do not measure over shirts or slacks. Hold tape measure close but not tight against body.
Bust: Measure across fullest part of bust/chest keeping arms relaxed at sides. Keep tape measure straight and parallel to the floor.
Waist: Measure at your natural waistline at its smallest part.