This is a 'cold-process' using lye (caustic soda), which is required to turn the oils into soap. It will evaporate over the curing process so will not be in the final product! Although caustic soda is highly corrosive it can be used with ease when following safe and sensible steps.
Check out the following recipe which is an easy guide for beginners, I've been using this recipe for over a year for body and hair (no conditioner needed either) - happy homesteading! :)