I know this has been done before, but I thought I would document the latest batch of soap I've made. Hopefully this instructable should give you some practical hints as well as help you with the theory of making soap from leftover fat.
Soap makes a unique and personal gift, especially when it is home made. You can also sell your soap at a farmer's market or just use it yourself. And it's a great way to get rid of old grease and fat that would otherwise find it's way to sewers or landfills.
The process uses caustic chemicals, so it is slightly dangerous. But if you follow general safety guidelines and keep your wits you should be fine. You might make a mess, but it should be easy to clean up because most of the spills will be made of soap!
I got most of my info from this page
and this lye table
I was inspired by this instructable:http://www.instructables.com/id/How-to-Make-Bacon-Soap/?ALLSTEPS
Note: I would've gotten better pictures, but it's hard to use a camera with eye goggles and rubber gloves.