In this helpful video, Brent of Goobertown Hobbies recreates one of his painting ah-ha moments when he first realized how to paint highlights on objects that don't have edges.
Everyone new to miniature painting knows the joys of finally figuring out how to successfully paint undercoats/shading, basecoats, and highlights. And then the next level of being able to do competent edge highlighting and other final highlighting.
But then there's the next level of things like painting dimensionality on large, smooth surfaces and surfaces that don't really have discernible edges. In the video, Brent shows his process for tackling this aspect of mini painting. He runs through it (using some shield-wielding Warhammer lizardmen) in a way that should make it easy for painters of any intermediate skill to master.
I love Brent's calm and quiet demeanor (he's been called the Bob Ross of mini painting) and his chill approach to what can seem a daunting process: "We might not end up with exactly what we had in mind, but we'll probably end up someplace cool."