if the stain is fresh you may try applying kitty litter over the spot and then grind it in with a shoe. If that doesn't work or if the stain is older, i recommend making a paste of baking soda and water and applying that to the area and let dry.
after using either of these methods you will want to scrub the spot with a mild detergent and water. I use ivory dish soap. This will also help to pull out more of the stain. May take several repeats to get it all out.