You will need:
1 bar of soap (any kind you want)
1 cup of Borax
1 cup of washing soda
a big pot ( that holds more than 2 gallons)
a grater
a funnel
a long spoon
2 empty gallon jugs/containers
Grate your bar of soap into your pot.
Fill one gallon jug and pour water into pot with grated soap. Cook until the grated soap dissolves.
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Add the Borax and washing soda.
Bring to a boil.
Turn off the heat.
Add 1 gallon of cold water. Stir well.
Pour 1 gallon of your detergent into each container.
Now you have 2 gallons of homemade laundry detergent. I use 1/2 - 1 cup per load.
In the end I made about 3 gallons of laundry detergent for like $4!