The measures that appear next to the sizes of the products correspond to the length and width of the garments, that is, if the size "S" indicates "long 70 cm x width 48 cm", this means that the garment has A length of 70 cm and a width of 48 cm.
With these measures, the easiest way to not mistake when selecting your size is by measuring a garment similar to the ones you already have at home and selecting, for those measures, the one that will fit you best according to the look you are looking for .