XS S M L XL
Waist 11.5" 12.5" 13.5" 14.5" 15.5"
Hip 17.5" 18.5" 19.5" 20.5" 21.5"
Length (Longest) 28.5" 29" 29.5" 30" 30.5"

*Model is 1.68m, UK 6 (Waist 12.5", Hips 18.5") wears size S.

If you are in between size for hip, it is best recommended to size up. 

If you are in between size for waist, you can choose to size down if you would like to wear it higher-waist, otherwise you can size up to wear it lower-waist.

*In between sizes refers to your measurements falling between 2 sizes, example size S & M.