The reason why I haven't learned any sign language is because I'm sort of frozen, I guess? I know that I should learn Norwegian Sign Language (NTS), and I've found various resources for that such as Ingrid Strand, TegnTV, SignWiki, MineTegn TegnWiki (although the main page for MineTegn redirects to a page saying that the project has ceased operations, nyoro~n), Døveforbundet and their social media pages, a few shows on NRK, a few books at the library, and I've just now heard of the app Toleio which I intend to try after I finish writing this comment.
Edit: Yeah, Toleio seems pretty good thus far, but I'm always a bit skeptical of language learning gamification apps.
However, the specific, unique challenges posed by learning sign language in general and NTS in particular have left me wondering about how exactly I should approach the task. My current thought is that although I'd be going against what I've been told is respectful of the Deaf community, that I should prioritize learning to sign at all over learning NTS specifically. Which is to say that I should follow the same path that I used for learning spoken languages, where I start with a constructed sign language based on one or more natural sign languages, and use this constructed sign language as what I call a "boomerang language" for learning NTS — in the same way as learning Finnish could be a boomerang for Northern Sámi, Japanese for Chinese and Korean, Arabic for Tigrinya, and indeed my 2016 conlang was a boomerang for learning Russian.