To put a pose into free stuff for use in DAZ Studio just use the .dsb file, that is all that is needed, if you want poser users to be able to use it then you will have to export it from Studio as a pz2 using the poser exporter,  I have never used it but I am sure someone who has will come along and explain it. If not perhaps you cold contact Richard Hasseltine (sure hope I spelled that right). Richard has  a list of tuts that cover nearly all subjects.