Good reference pages on soap making
This one uses a
18 oz lye/5 cups distilled water/20 liquid cups olive oil (liquid soy oil would work.)
I don't eat soy oil, but it makes great soap, and its an easy freeby.
Trade your neighbor who gets food boxes, soap for oil.
Red devil lye soap recipe

I use:
1 can red devil lye 12 oz
2 1/2 pints cold spring water
2 "3 lb" cans soy shortening, {Gov't} (you can also use liquid soy oil.) 100 degrees

makes nice white soap.
1 cup borax (for lather) optional


Directions:
Melt fat or use liquid oil,
different container:
dissolve lye in water--let cool to 85 degrees,
Pour lye water into fat slowly, add borax
stir rapidly until trace (making raised streaks on surface) pour into mold
leave undisturbed 24 hrs (lid and insulation-Blankets, improves saponification)
cut soon into bars before it gets real hard. As soon as your finger won't push down into it.
I oil my mold to make it easier to get out.
Let cure at least 2 weeks before using.
I get 40 2" x 3" x 3/4" bars.
enough for 2 years.
Can be grated for laundry soap if desired.

Be careful lye is dangerous, Read all the safety stuff on the two links above.
I stir it with a whisk in a variable speed drill to include air bubbles and make a 
soap that floats.