How to make watch faces

I have a samsung smartwatch, and I'd like to make watchfaces for it. The problem is that I tried once and I couldn't find any documentation, not version or basically anything. Somehow, I forgot how, but I managed to print text on a background picture. It was very frankenstein-like.

I'd like to start over with proper everything, so I came here asking on the offchance that any of you can help me with at least documentations. I remember it being in java, however if I can use other languages I would. My mate got the idea to somehow render a webview, because that atleast it's codeable, problem is I have no Idea how to render anything.

Can someone give me links to usable up-to-date docs? Or pre-written webview? I wasn't able to find anything.