Qualifications
Qualifications? Other than being totally awesome and really good at Rubik's Cubes?
Uh, yeah. You're going to need a lot of qualifications before you can find a job using your cryptography skills. To even be considered for an entry-level crypto job, you'll need a BS in computer science, math, or engineering. To actually get the job, though, you'll need a carefully curated CV with an impressive number of internships. The National Security Agency and Central Intelligence Agency both offer opportunities worth looking into. To get you going, the NSA even has a nice, long list of internships.
And before you get too cocky, sure, internships are cute and all...but eventually, you're going to need a higher-level degree: a Master's of Science, or preferably a Ph.D. in cryptography.
While you're doing that, make sure to polish up your language skills—computer programming and non-computer programming. A successful, employed crypto should know how to communicate with computers and people.