You Can Do It!
You may have thought of grating and dissolving solid soap to make liquid soap. You may have even tried it and found yourself with a slimy, sticky mess that separates almost immediately, then dries to a crust. Obviously, this method doesn't work. But by using the hot-process soap method with potassium hydroxide as the caustic, you can make beautifully transparent, nonseparating liquid soap from scratch.
It is a good idea to make cold-process soap first, then do some hot-process projects before you tackle liquid soap. It's not that it's terribly difficult, but there are more variables, and the more secure you are in basic soapmaking the easier it will be.
Again, we look to innovator Catherine Failor for guidance. Her book
Measure, measure, measure.
Don't assume that what's in the soapmaking books is gospel. Many of my problems with soapmaking came because of the 90°F pour temperature, which seemed to be written in stone in most soap books. Most problems people have come from too low a pour temperature and the consequential poor saponification.
I pour my cold-process soaps between 120°F and 130°F, especially in winter.
Just remember that most soap throughout history has been boiled, not cold-processed.
Don't be afraid to experiment.
