LISTEN THE BEST THING TO DO IS TO HAVE A PEEK INTO HER LINGERIE DRAWER AND HAVE A LOOK TO SEE THE STYLES AND SHAPES SHE LIKES. 
BY HAVING A LOOK AT HER EXISTING LINGERIE, IT'S ALSO EASIER TO LOOK AT THE SIZING SO YOU'RE NOT TRYING TO BUY IT BLIND. THERE'S NOTHING WORSE THAN BUYING AN INCORRECT SIZE, UGH SOOOO ANNOYING.
REMEMBER, DON’T GET FISHING AROUND IN HER LINGERIE DRAWER, THAT MAY CAUSE SOME CONFUSION AND EMBARRASSMENT. WITH THAT BEING SAID, I SUGGESTS STICKING TO OPTIONS WITH EASIER SIZING.
FOR INSTANCE, THERE ARE LINGERIE OPTIONS, SUCH AS SEXY TEDDIES, THAT ARE SIZED BY DRESS SIZES, WHICH ARE A LOT EASIER TO GAUGE THAN UNDER-WIRED BRAS AND LOW CUT PANTIES.
HOWEVER, IF HER STYLE IS MORE RISQUÉ THEN THERE’S ALWAYS THE LINGERIE GIFT CARD OPTION.