Knurling is done by a knurler. This mechanical device has rollers with the posative side of your knurl, the knob is pushed tightly against these to make the knurling impression as it is rotated between the rollers.

Flat brass parts can be easy to make from stock materials but is a pain to reproduce perfectly in pairs or in number unless you have some mechanical experiance and access to a shop for the tools you'll need. I cheated making slides on a computerized sign machine, same only smaller as a CNC router, a few years ago when I worked in a shop that had one.