CHEST : Place tape measure 1 inch under the arms and measure horizontally.
BELLY : Place tape measure where stomach is strongest (about the 3rd button from the bottom of a shirt) and measure horizontally.
BODY LENGTH : Place tape measure next to the collar and measure vertically to the bottom of the garment.
SLEEVE LENGTH : This measure is taken in two steps. First, place tape measure in the center of the back, just below the collar, and measure horizontally to the shoulder seam. Next, measure from the shoulder seam to the bottom of the sleeve. The sum of these two measurements gives you the length of the sleeves.