The longer a stain sits, the harder it becomes to remove, so if you spill something greasy on suede, act immediately to blot it. If you are not at home, soak up all the oil you can with a napkin. Later, use the cornstarch method to lift the oily stain out of the suede.
As soon as possible after the spill, generously sprinkle cornstarch onto the stain to soak up the oil. Gently press the powder onto the stain and let it sit for about 10 minutes before brushing it off with a dry cloth or suede brush. Repeat the cornstarch application until nearly all the oil has been lifted. Pour a little vinegar onto a soft cloth and lightly dab the stain. After letting the suede dry, brush it with a suede brush.
A commercial leather goods degreaser may also be effective. Follow the manufacturer's instructions to remove the oil stain. Alternatively, you can gently rub light stains with an art gum eraser. Do not use ordinary pink erasers, which may stain the suede further.
If the nap of the suede has flattened after cleaning with any of the methods outlined here, hold the affected area over a pot of steaming water. The steam will revive and fluff up the nap. Take care to not get the suede wet during this process.
If the stain remains, consider taking the item to a dry cleaner for professional cleaning.
Do not use soap and water on suede, because the water may spread the stain and even permanently damage the leather. If the stain is old, removal may be impossible.