The tutorial is in "The Art of Animation:Master" book you got either as a book or as a pdf file when you bought A:M
That version is somewhat condensed. Colin freeman wrote it originally and although his site is down, you can still get the whole version on the wayback machine
http://web.archive.org/web/20071226033127/.../tutorials.html
it also has tuts on all the other body parts.
I think he directs you to use too many CPs in the first splines, but that's just my preference, you can always thin it out later.