Re Jamie’s point, you could set up a Shopify storefront and drive traffic from Facebook, Youtube channel and such. I know that many people (as well as mysef) are afraid of not being in a marketplace where you are basically guaranteed sales (or not! read Etsy forums), but that’s how all the big guys do it. Who knows, maybe you are the next marketing genius. Just try!
This website has an app and actually offers accredited degrees… Certification, diploma, associate, master, etc…it even offers comprehensive lessons on the psychology of consumers if you truly want to get in-depth. I found that reading jewelry blogs give you great info and sort of show you how they market themselves!