YAFRAY HELP

I need help with yafray. I need the basics to render with it and how to do focal blur with it.

As for as I know there are two ways to do it , a post production effect and
the new depth of field for 2.34 when yafray render is selected for the camera ,I would pick
the second,it gave the look I needed and I never got into the first to much.

Yeah i used the first and it was not good
thanks for the help