There were some interesting technologies before computer aided design in sign shops. When I was a kid one of my first jobs was silk-screening custom-made signs (like in those photos) and stickers. Much of it was done with light (UV?)-sensitive film techniques. A master was created carefully letter by letter from a bunch of letter 'stickers' [https://en.wikipedia.org/wiki/Letraset], then the light-sensitive film was applied to the silk screen, and the master laid on to it and a lamp shone on it for a few minutes. The parts NOT exposed to the light (behind the letters) were capable of being washed away with a solvent of some sort (water in some cases if I remember correctly), leaving a very high resolution stencil that would be used to print onto whatever material desired, with a number of different types of inks. Pulling a squeegee and stacking hundreds of placards for drying was my summer job for several years. :)

For the really custom stuff, our commercial artists were amazingly talented with both brush and penknife. Some of those guys could paint lettering by hand that was incredibly consistent and amazingly fast.