I got this recipe from:
http://www.thefarmersnest.com/2011/11/liquid-hand-soap-diy.html
Cheese grater (from the dollar store)
2 Tablespoons of Liquid Glycerin (found in the band aid section at any drugstore or grocery store)
1 – 8 oz bar of soap
1 gallon of water
Grate the entire bar of soap. Fill a pot with 1 gallon of distilled water and add the soap shavings.
Add 2 Tablespoons of liquid glycerin and turn the heat to medium/high and stir until the soap dissolves.
Leave it alone to cool for at least 10-12 hours. It begins to cloud up after 3-4 hours.
After it has cooled completely around 12 hours later it will harden and look like liquid soap.
If the soap is harder than it should be you can take some beaters and blend it while adding just a little bit of water until the consistency is more like liquid soap.