I taught a class on the heraldic achievement: its history and development, and how it should be drawn. I first taught the class at Collegium Caidis in 2018, and then I expanded on it for the Known World Heraldic and Scribal Symposium in 2019.
As promised, here’s the handout of my class, in PDF form. Download as you wish, but please, don’t copy and distribute it. Rather, give people a link to this page. I’d appreciate it.