Measure from where the shoulder seam meets the sleeve on one side to another side.
Measure from the stitches below the armpits on one side to another.
Measure from where the shoulder seam meets the collar to the hem.
Measure from where the shoulder seam meets armhole to the cuff.
Measure the circumference over the fullest part of your bust.
Measure your waist at the thinnest place.
Measure the fullest part of your hips.