A couple of bras being hand-washed in a white basin. We’ve all been there: You reach for your favorite bra as you’re getting dressed, and you realize you can’t remember the last time you washed it.

Let your bra soak for about 15 minutes. This gives the detergent time to break down oils and remove dirt without damaging the fabric. For tough stains, you can opt to use a soft toothbrush to work on ...