To make powdered laundry soap at home, use a bar of soap, 1 cup of borax and 1 cup of washing soda. Grate the bar of soap using a box grater or food processor, and mix the ingredients well. This low-sudsing laundry soap works well for high-efficiency washing machines.
While any type of bar soap works, some makers prefer to use Fels Naptha, an oil-free soap made especially for laundry use. Most stores stock it near the stain removal sprays in the laundry aisle and not with the hand soaps. They also usually stock washing soda and borax in the same aisle.
After mixing the laundry soap, store it in an airtight, waterproof container. Add a few drops of essential oil if you prefer a scented detergent. Use approximately 1 tablespoon of the soap for a high-efficiency washing machine or 2 tablespoons for regular machines. Add one to two scoops of oxygen bleach to the wash cycle to boost the cleaning power of the detergent. For whites that look dingy, try adding liquid bluing to the machine.
Use distilled white vinegar as a natural fabric softener, and rinse aid with each load. Pour the vinegar into the fabric softener dispenser, or add it to the last rinse cycle. The vinegar smell dissipates when the clothes dry.