Most candidates at Mercer independently break into small groups to study. He also points out the exam material for candidates with an insurance company is different from consulting. For students still in college or university, he recommends internships and co-ops along with a wide variety of classes. Focus on the finance side and get as broad a liberal arts background as you can. I spend a lot of time marking up and editing memos to clients.
Communication skills are at least as important as the tech side.