CRM - Crew or Cockpit Resource Management is the art of getting the best out of all the people, equipment and other resources available to you at all times. It's often compressed into meaning the cross-cockpit relationship netween Captain and FO, but there's far more to it than that. At its most expansive, it includes cockpit ergonomics, company procedures and many other apparently peripheral things which demonstrably affect a crew's performance in times of stress.
The CAA/JAA prescribe what books you need to study to pass their exams, and your airline will have its own CRM training procedures when you get there. In the mean time, just think about how you would get the best out of a person in the other seat who's tired, fed up with the company, just been abandoned by girlfriend/husband/lover, crashed the car and has a £15000 overdraft. That should get you thinking along the right lines!