Sprinkle talcum powder over the oil stain. Let it sit overnight to give the talcum powder time to pull the oil from the leather.
Sweep the talcum powder off the leather in the morning, and throw it away.
Mix three drops liquid dish soap with 1 cup water.
Rub the soapy water over the stain until it is gone.
Rinse the leather, and immediately dry it with a clean cloth. Never let leather air dry as this will encourage it to dry out and crack; it may also leave water marks on the leather.
Sprinkle cornstarch over the oil stain.
Brush the cornstarch into the suede with a clean and dry toothbrush.
Let the cornstarch sit overnight to give it time to soak up the oil.
Discard the used cornstarch.
Blot a leather degreaser directly on the human oil stain on the unfinished leather. Work from the edges of the stain, and apply as much as needed to remove the stain. Use a degreaser designed specifically for unfinished leather.