https://www.udemy.com/unity-shaders/ is a course that I highly recommend ( if it is by Penny de Byl or Holistic3d, if not then it's the wrong course : / ) it is a one-time payment of 9.99$ (or something like that) for lifetime, and you can take it whenever you feel like doing it. I own this course and LOL I haven't even had the time to do it. I can say it is really good though! You learn some pretty good stuff! I have several of Penny's other courses.. actually all of them except for 2 I think. Just take it, there's like a 30 day money back if you don't like it so yeah