Measure your chest with the measuring tape underneath your arms, across the shoulder blades, and over the largest part of your chest. The chest measurement will likely be the size of your coat. Measure around your chest at the highest point of your shoulder blades including the fullest part of your arms. If this is 7 inches or more than your chest, order the next largest size coat for comfort.
Dress pants are to be worn above the hipbone on the natural waist for a proper fit. With the measuring tape snug to your body, measure the waist near your navel. This measurement is your waist size.
To find your inseam, measure a similar pant that fits you well. Measure the pant from the top inner thigh to the bottom of the hem. The number of inches to the nearest ½ inch is your inseam. Alternatively, measure from the top inner thigh down to the bottom where your pants should end, at the top of your shoe in front and just above your heel in back.