<human>:  How do I remove a stain from my white shirt?
<bot>: There are many ways to remove a stain from a white shirt. One option is to use a commercial stain remover product, which you can buy in most grocery stores or supermarkets. Alternatively, you can make your own stain remover at home with baking soda and some warm water. Simply mix the baking soda into the warm water and apply it to the stain. Let it sit for a few minutes, then rinse it off with cold water. Once the stain is gone, you can wash the shirt as you normally would.