The PCB was etched using tone transfer method. The board layout was printed on a couche paper sheet from a magazine.
The board was then etched, drilled and trimmed.
A final touch was adding a silver cover over the copper using TP056E. This stuff really works. I have boards without apparent oxidation that were protected in 2008 when I bought this stuff that now has expired for over 6 years and still work, not quite as good than before it expired though.