You can also use dish detergent to get grease out of clothing. Look for a brand which is designed to cut through grease, like Dawn. Rub the detergent lightly into the grease stain to pretreat it, or simply run the clothing through the laundry with a few squirts of the dish detergent. Many massage therapists use dish detergents on their sheets to get rid of oil stains, as do restaurant workers and mechanics.
There are also a few more obscure tricks, which this author has not personally tested. Baby powder is supposed to be effective if left on overnight, as are products Some people swear by Cheese Whiz?, while others claim that a can of Coca Cola? or Pepsi? in the wash can remove grease stains. Shampoo has also been known to get grease out of clothing, especially shampoos designed for oily hair.
In all cases, you should wash greasy clothing separately from other clothing to avoid spreading the stain. This is also important when you have used something to pretreat the laundry, as the pretreatment may smell odd; many people wash greasy clothing once with the pretreatment and again on a regular cycle to get rid of the smell. You should also check the clothing to see if the grease stain has been removed before running it through the dryer, as the dryer can set the stain, making it impossible to remove.