Neck Measurement Measure around the base of your neck and add between two to three fingers to this measurement to make sure the collar won't be too tight at the closure. Chest Measurement Measure the widest part of the chest with a tape measure tucked just underneath the armpit. Waist Measurement Measure round the narrowest point of your waist. Sleeve Measurement Measure from the center back of the neck to the shoulder then from the shoulder down to the wrist bone.