This is a pretty common question – I probably get asked it a couple of times a month.  In addition to at least two hours of reading each week (minimum) and paying attention to current events, in 2016, I had more than 100 hours of formal training (online, webconference or in person) in these areas:

Healthcare.gov  (8 hours)

Specific Carrier and Plan Training (25 hours)

Regulations and changes (24 hours)

Retirement Plans and Investments (24 hours)

General Knowledge (21 hours)