Flamenco dance outfits are meant to have a close fit. Therefore the patterns are designed with practically no ease, i.e. the measurements of the garment are the same as the body measurements. You need to take this into account when selecting your size and choose the bigger one in case of doubt.
How to Take Your Measurements
Waist: Measure around your natural waist line
Hip: Measure around the fullest part of your body, usually approx. 22-25cm below the waist