For dresses, measure 1 through 14 and A, B, C.
Skirts would be 2 through 6, and 12.
For sleeves, include 15 through 20 and D, E.
For pants: 2 through 6, 12, 21 through 24, all Fs, and G.
H is just for jumpsuits.
Or keep it easy and measure them all!
Use the space on the bottom to add relevant sizing information, for example: is perfect size 6 pant at Banana Republic; left shoulder higher; gave birth 12/2013. (None of these things are true about me.)