SLEEVE: Measure from the middle of the back of your neck, over your shoulder, over your elbow, ending at your wrist.
WAIST: Measure the smallest point of your waist all the way around.
INSEAM: Measure from your crotch down to the top of your foot. 
 

Women's Regular Fit Size Chart

Size Chest Sleeve Waist Hip
2XS 32" 29.75" 26.5" 35.5"
XS 33" 30" 27.5" 36.5"
S 34" - 35" 30.25" - 30.375" 28.5" - 29.5" 37.5" - 38.5"
M 36" - 37" 30.5" - 30.75" 30.5" - 31.5" 39.5" - 40"
L 38.5" - 40" 31" - 31.125" 33" - 34.5" 42" - 43.5"
XL 41.5" - 43.5" 31.125" - 31.625" 36" - 38" 45" - 47"
2XL 45.5" - 47.5" 31.875" - 32.125" 40" - 42" 49" - 51"
*all measurements done in inches (")