The hardest part probably is the “Printer Model Selection”. In former years the situation was difficult, because there were hardly any drivers to find. Now it is, because there are too many, with some of them very good, but many quite broken.
If you have a current “database” of available drivers on your system, select the manufacturer in the left part of the window first, then the device model in the right part. This split window shows all PPDs found by CUPS in its standard repository of installable PPDs. This repository normally is /usr/share/cups/model/. If you want your driver found automatically by CUPS and KDEPrint, throw it in there.