YouTube videos can be a good source of info and good technique, you just have to be careful though. Anyone can upload and not all techniques are valid, so try to vet as much as you can the source of the video.
Not all are like that, I'm not trying to say that they are (even more so since I'm in the process of uploading videos), but some are better then others and some are just out there with Pluto.
The way that I learned (and I started hand sewing and hand embroidery a good bit before I started doing it professionally) was almost exclusively focusing on technique. Didn't have to worry about pulling out my mistakes initially. Then when technique was down good, then I had to rip out my mistakes. Main focus was to keep interested and focused on learning technique, always having to pull out mistakes will frustrate anyone, now as I was a kid that would have been really quick, didn't have much of attention span back then.
Trial and error and just getting on the machine and doing is going to be the only way to learn, but I would make sure that you get a good source to learn from. I was lucky in that regard.
