This is the crux of the matter, the choice of size is crucial. At Luxury Alley, we do the exchanges for free, but the best thing is obviously to aim right from the beginning.
For sexy lingerie, it's easy. You just have to choose among sizes like S or XL. Sometimes hybrids such as SM or LXL are offered, they will go respectively to sizes S and M as well as L and XL for example. In order to find out his size, go to his wardrobe incognito to find his usual size. Choose a pair of pants, a skirt or a dress she is wearing right now and find the label. Lift up the waist and keep it in mind. On all our product sheets, you will have the correspondences of the style
For fine lingerie, such as bras and some corset or babydolls, it will be in cup size. 90B or 95C, etc... The only option in this case is to find one of her bras (also recent) to raise the size.
In case of doubt, the top size is the best choice, as lingerie is very often stretchy. The customer service is also available to help you make the right choice, don't pass up good advice...