You can learn from video's, but its best to have a teacher. I learned it in college. Then I worked for a taxidermists part time as a 2nd job. Its not really a technique that can be mastered easily. Its a art that takes skills, and patients. Its one those deals the more you do the better you get at it. Your first few mounts will look terrible to you yrs from now. I have mounts on family's walls I beg them to take down.Man I sucked back then, hahaha.
You also need the right tools, and some modern tools make the work easier, and better. I started with a hand heldfleshing knife & home made beam. You can also do some basic tans yourself at home, but many send them out now.
Basically what I'm trying to tell you is good quality work isn't as easy as most would think. So if its something you seriously want to get into. I'd look to a teacher, or shop for the experience.