A good washing with laundry detergent can soften the lace. You only need a small amount of detergent to wash the bra. The laundry detergent helps remove whatever chemical the manufacturer used to make the bra -- such as starch. Select a laundry detergent without bleach. The bleach can change the color of the lace.
Sometimes washing the bra in laundry detergent doesn’t soften the bra enough. If this happens, add a small amount of fabric softener to the rinse cycle or after you hand wash it with detergent. The fabric softener can make the lace more comfortable.
For those who do not like to use fabric softeners because of chemicals or an allergy, try a white distilled vinegar rinse. The vinegar rinse -- 1/4 cup per bra -- helps soften the lace without discoloring or adding chemicals. The odor from the vinegar disappears as it dries. This rinse is also helpful for removing odor or stains from the lace bra.
A lace bra won’t feel soft if you don’t rinse it thoroughly. Depending on the material make-up of the bra, it may absorb the laundry detergent or softener. Foam padding, for example, can soak up the soap. The soap can also cling to the tiny holes in the lace itself. This is why it’s vital to rinse the bra until the water contains no soap bubbles. You may need to press the padded areas of the lace bra gently to ensure that all of the soap rinses from the fabric. Another way to ensure that detergent residue doesn’t cause the lace to feel stiff or rough is to use no more than 1/4 teaspoon of laundry detergent and fabric softener per bra.