First you will grate your bar of soap into your sauce pan.
Then you will fill the sauce pan with water. Heat to a light boil and stir constantly as the soap dissolves. ***DO NOT LEAVE UNATTENDED*** It can boil over quick. Or so I am told I never left it. When the soap is dissolved set aside.
Fill your bucket with 4 1/2 gallons of HOT tap water. As hot as you can get it. Add you soap soup, your borax and washing soda. Stir until well mixed.
Leave to cool for 24 hours. I finished making mine at about 8:30 PM and it was ready to go around 10 am the next day. I know that is not 24 hours but I needed clean cloths. :) It is supposed to look like this when it is done.
Then I stirred it up well and added it to my left over laundry soap bottle. Leave room to shake it up before you use it. You will need to shake it up before each use as it gells up.
I use 2 to 3 cap fulls for each extra large load I run. This come out to 1 to 1 1/2 cups.
You probably want to know cost, huh? Well I would say probably about $7 to start, with the average 5 gallon bucket full maybe costing $2 to make. Heck I pay around $2.99 for that little bottle of all and that last only two weeks.