A few years after my first Heraldic Drawing class, I co-taught a class at a KWHSS in Caid, alongside Dame Zenobia Naphtali, Black Stag Herald. We documented the sorts of monster used in period coats of arms (a much smaller set than those used in badges), and I made up a handout on how to draw them.
It includes tips on how to draw beasts and birds as well, and I think I explain those charges better than I did in my Heraldic Drawing handout. Anyway, it’s now available to you here: Drawing Heraldic Monsters.
As before, feel free to download for your own use, but do not distribute: provide a link to Mistholme, and encourage folks to visit me. The more the merrier.