One more time, some lobbyists try to regulate the Internet with some of the stupidest laws or rules. SOPA (in US) is again one of this tentative to break down the freedom of citizen worldwide to preserve some archaic business model. As I have a preference for concrete action leading to a direct social improvement, I'll explain how to do soap (it's better than SOPA and more useful, please note the clever inversion of the letters). My soap recipe is released under the public domain dedication license (CC0).
Doing soap is a chemical process that requires your full operating brain. Especially that you'll use sodium hydroxide that is a corrosive substance. So respect the proportions, the process and read the whole process multiple times before doing it. Wearing protective gloves and goggles is highly recommended. Avoid to use kitchen instruments in aluminum as it will be attacked by the sodium hydroxide.
Doing soap is one of the first chemical process discovered by the humanity. The process is called saponification that is done by using a base to hydrolyze the triglycerides contained in the fats (organic or animal). This process generates a fatty acid salt along with the glycerol (the greasy touch of the soap). Each fat has a specific value for its saponification. The saponification value (usually called SAP in saponification tables) is expressed by the required volume of base (usually sodium hydroxide) to saponify 1 gram of fat. The saponification value is reduced to keep the resulting soap a bit fat (what is called the "excess fat"). I find it even convenient to keep a "safety" bound to ensure that the hydrolyze is complete and used the whole sodium hydroxide.
So that's the basis if you want to build your own soap, there are other rules to consider but for this recipe this is enough. In my case, I use olive oil as a fat. Easy to find and I have a preference for organic olive oil (to ensure that the oil producer is taking care of its environment). But you can use non-organic olive oil too (it's usually cheaper).