A while ago a friend told me she makes her own laundry soap so I decided to try it. My kids have really sensitive skin so it helps them and it is a lot cheaper than store bought stuff.Ingredients:
1 Bar of Soap (I have used just generic stuff with no scents or colors and I have used Fels-Naptha.)
1 cup Washing Soda
1/2 cup Borax
(You should be able to find all of this in the laundry soap section of most stores or on Amazon.
I chop the bar of soap up and throw it and all of the rest of the ingredients in my blender. Then I dump in an old ice cream bucket. Don't breath in the dust and make sure the container is airtight. It only takes 1 Tbsp. per load.
If you prefer you can also just cook it on low heat with some water to make it liquid laundry soap. You are done when the soap is dissolved into the mixture.