Omega Cal 620 hairspring bent

If you want to learn how to repair balances, get some good off brand (and fairly large) movements in tip top shape. I like A Schild, but anything from ETA, Felsa, or the other myriad of Swiss manufactures who were active between 1940 and 1970.

It is best to start with a working watch what keeps time. That way one learns what the results should be. Get watches by the dozen and work with 100s of them.

Ideally one would also learn in person from some one who can fill in the gaps that not book or video could do. Books and Videos are great for theory. They do not tell you things like how high the bench should be. How to hold tools and such. One is going to be spending the time sitting for hours if not days or months staring at what was called the 144, which is the square foot in inches that becomes ones world. One also has to train the muscles to work for long hours in an Alice and wonderland world where the center of gravity is not what you think. Where static attraction and magnetic fields outweighs the mass of the part. Air has mass too which also outweighs the parts.

Another note about books most were written before the 1930s and deal with pocket watches, large movements and stuff what could be manufactured in the fireplace or on the stove cook top.

Starting with a tiny Ladies movement, will only lead to frustration and remorse.