To KS' statement I would add - read not only the regs but also the footnotes and the interpretations/staff commentary. A lot of times, things that you have questions on will be addressed in those areas.
And get to know your primary regulator - a lot of times, they can be helpful (no, really!) if you have questions or just want to bounce something off them.
I disbelieved what he was saying so hard, I probably created an alternate universe where it wasn't true.