Either ExtUtils::XSBuilder or h2xs will do most of the work for you reading the header(s) and or C source file(s) and writing the glue code. With XSBuilder see the POD here. While either of these will do most of the work you will be very lucky if you don't have to fine tune it yourself. HTH.

As far as teaching you how to do your paid work goes by leading you by the hand through it forgive me for the lack of enthusiasm.