Where can I learn to create wire drawing dies?

These are the only kind of drawing dies I am familiar with. Are you working with something different? What specific portions of the design are causing trouble?

I've only had to draw a few, but it came down to trial and error for me with getting the resulting wire to the correct diameter. I'm sure someone that does this all day has some tricks and guidelines to speed up the process and get the desired diameter quickly.

Some additional images can be found here: https://clipartxtras.com/categories/view/91e8b5a6e85bac5367b5c713a7ccc92d4b936492/wire-drawing-die-profile.html

I'm sure they are not 100% accurate for building a model, but I used them mainly to get a grip on the nomenclature before talking to a shop that does wire drawing. If I know the lingo, they won't think i'm a complete idiot ;)