Keep Your Loads Light

Be very careful not to overstuff your washing machine when you're throwing your bras in. Heavy items can do a lot of damage to your undergarments -- especially if you wear underwire bras. "No jeans, no towels, no sheets," says Clarke. "These items are too heavy. It'll ruin the bra to dump everything [in] together."
Nethero goes a step further, recommending that you not only stick to small laundry loads, but only wash Lycra items together. "Save up things like tights, panties, exercise tops and shorts," she said. "Lycra is subject to degradation if you don't care for it properly."
Always Hang Dry

Although our experts were willing to stray from the "always hand wash" rule, they insisted that hang drying your bras is the only way to go. "Never ever put a bra in the dryer," said Nethero. Kirby also said that extreme heat -- which is used in a mechanical dryer -- was a major problem when it came to caring for delicate items.
Instead, hang dry your bras by the strap or lay them to dry on a towel, cups facing up (i.e. nipples facing up). And make sure that your bras are properly reshaped before you dry them.
"If [your bra cup] gets dented [while being washed], just take your fingers and gently smooth it out so that it looks like a cup again," said Boorstein.