well first you need a modeling program of which theres are dozens ranging from free (wings3d) to resaonable (hex, carrara, c4d) to bloody expensive (maya).

then the the model needs mapping .. either in your modeling program or with another lik Uvmapper or uvlayout

then grouping .. either in uvmapper or AutoGroupEditor

Then theres the rigging .. generally inside poser but not always.

thats the super simple overview .. t'aint as easy as it sounds. Poser is particular about its models.

I suggest you find a copy of 'poser5 figure secrets' by BL render. it covers modeling for poser and rigging issues. I keep mine by my desk to look up weird issues when a leg falls off a model and so forth :)

Lyrra