You can learn by studying or learn by doing. I've found that for some, myself included, immersing yourself in a new domain as part of a job (and maybe a career

You can learn by studying or learn by doing. I've found that for some, myself included, immersing yourself in a new domain as part of a job (and maybe a career) is the best way for me to grow quickly. My hobby is economics and I study that every day. My career is life sciences research, and I practice that every workday and study almost every day. The level of competence I have in my career domain is vastly higher than my hobby domain, even if I like my hobby a bit more perhaps.