I have made my own laundry detergent for years so I recently found a pin for DIY Liquid hand soap and thought, why not? So, as the link above states, you need a bar of soap and liquid glycerin.
I had trouble finding the liquid glycerin. It was not at my local grocery store but Walmart did have it near their bandaids section. I decided to try Lavender Pure-castile soap. Follow the directions as given in the link and by the end of the day you have a whole gallon of liquid hand soap. Super simple and super cost effective.
How it turned out: The tutorial mentions the thickness of the soap as it hardens. I thought I addressed this prior to pouring it into my gallon container but as I went to pour it into my soap container this morning it was so thick it would not pour. So I squeezed some out into a bowl and added more hot water. It seems to have helped but isn't quite the consistency I wanted...I must have done something wrong! But, overall it gave me lots and lots of soap and if I can get the consistency issue corrected I would say it was well worth the time and the little money to create this much liquid soap.