You don't need to get six cups worth...you can find lots of great recipes online..
http://millersoap.com/ has some fun recipes...
this is the normal basic recipe I use...
14 oz water
6 oz lye
12 oz coconut oil
8 oz palm oil
20 oz olive oil
to make it a milk soap you can just use 7 oz of water when making the lye water then add 7 oz of bm at trace.
milk soaps are VERY tempermental it can easily go icky fast..the miller site I posted should have some info on it but the easiest way is to add the milk at trace as when you add the lye it heats very quickly and the milk can curdle which makes it smell kind of weird.
I would highly recommend trying the adding at trace method unless you are pretty experienced at soaping and even then a lot of people have problems. I post at a soaping bb and people are always having tragedies with their milk soaps.
sorry for the grammer problems...nakking....
I will bump the other soaping thread..it mentions a little about using milk or cream