What are the hands-on skills that mechanical engineering craftsmen possess, and how can one gain such skills?

Hands-on skills are gained from…wait for it…..hands-on-experience. You build up those skills over time from actually doing things. Driving a car is a hands-on skill. The more you do it the more likely you will get better at it. Craftsmen, teachers, doctors, pilots, ditch diggers. They all improve by doing.