Homemade Laundry Detergent! Homemade laundry soap is cheap. I've been making it a couple years now. It's like $1 a gallon! Here's my plan for neighbor gifts for Christmas this year! 1 quart of soap...25 cents, mason jar...about 70 cents... Under $1! :) And super useful...and not fattening! (Feel FREE to copy my genius idea!) So here is what you need: Fels Naptha soap (found in the laundry soap aisle at the store...less than $2) Super Washing Soda (huge box about $5) 20 Mule Team Borax (about $5 a box) Grate your entire bar of soap. Easy! Add soap to large pot of 6 cups of hot water... with the heat on medium/high. Once the soap dissolves... add 1 1/2 cup of washing soda and 1 1/2 cup of borax... add 12 cups of water...don't breath in the steam! Pour into a 5 gallon bucket and add about 4 gallons of water. stir well. It wi...