Wipe off as much of the gravy stain as possible with an absorbent cloth without smearing it further.
Read the label on the satin garment. Many satin fabrics are machine washable, but others are delicate or have embellishments that require special care. If the label states it is dry clean only, take it to a reputable store as soon as possible. Tell the clerk it is a gravy stain so the store can use the appropriate dry cleaning treatment to increase the chances that the cleaning will work.
Treat the satin fabric with a pretreatment stain remover that does not have bleach as an ingredient right away if it is machine washable. Use one that is petroleum or detergent based for the best results.
Wash the satin fabric in the hottest water it can withstand according to the fabric care label. Nylon and polyester satins require that you wash them on the gentle cycle in the washing machine, as suggested by J & O Fabrics. Cool or warm water is typically the recommended temperature.
Add bleach-free laundry detergent to the washing machine and turn it on. Use a detergent that is formulated for delicate fabrics.
Inspect the satin fabric for any remaining gravy stain once the cycle is complete. If there is still a stain, repeat the steps until the stain had disappeared.
Dry the satin once the gravy stain is gone. Roll it up in a towel to absorb excess moisture. Hanging the garment up to dry is typically recommended on the garment label.