They're Wiccan terms, so you're going to bump into magick when you go look for more information. There's plenty of tulpa-like aound though, people just obviously have their own reasonings as to what they are.
Visualization isn't necessary of course and some people probably work better with something other than their sight, but I do find it very useful, especially early on when you're in that pre-vocal stage. For many other communities based around tupper-likes, imposition is super important too because it's a hallucination which makes them think it's real and magical and such. But thought control - assuming you mean the same I do - I really think you should be at least trying to get good at. I think that's what I have always been telling people to do and we did even remind people in the FAQ on this site that everything weird that happens in your head is your imagination and under your control.
I wouldn't say you have to master these things when starting tulpaforcing, though of course better skills help. But you can practice while you force, so it's two birds with one stone. Only if you find your skills completely lacking would I ever tell you to just work on bettering the skills without involving forcing to it as well, but normally, I think you get all the practice you need as you force.
