When measuring for your jacket and waistcoat, your chest measurement should be taken across the widest part of your chest. This should be a loose measurement taken from under the arms and over the shoulder blades. When taking your chest measurement, your arms should hang loosely at your sides for the most natural measurement. We will also require your sleeve length for your jacket. When measuring your sleeve length, measure from the edge of your shoulder down to your wrist and where your jacket cuff would sit.