Try to flush out the staining agent as quickly as possible with cold water first. Get as much of the stain out as possible, then use a mild hand soap and dab the rest out with a towel. Tougher stains can be removed with a body soap such as Ivory.
Know Your Fabric
To be sure that a detergent is suitable, sample a section of the garment that is not readily seen. The best place to test the fabric of a garment is the inside seam. Make sure the detergent does not create its own stain, remove any fabric dyes or harm the fabric. Silk should never be treated abrasively by rubbing it.
What To Do (and Not to Do)
Do not place garments with a stain in a closet, where warmth and heat can set the stain deeper. Never iron clothes that have a stain. When cleaning a stain, do not rub the garment. Instead blot or dab at the garment with a clean cloth. Even if you remove the stain, take the item to the cleaner as soon as possible. Dry cleaners have the solvents to remove most stains effectively without harming the fabric.