How to Make Homemade Laundry Soap (Liquid or Powder ...- how to make washing powder washing soap lemon washing soap powder ,May 01, 2019·Instructions. Powder Instructions; Use a cheese grater to grate or shred the bar soap. In a large bowl, mix together the borax, washing soda, and baking soda.How to Make Organic Dry Powder Laundry Detergent | Home ...Combine the soap flakes in a mixing bowl with 1/4 cup of baking soda or washing soda, and 1/2 cup of pure borax. 3 Stir the ingredients with a wooden spoon until they're thoroughly combined.