What career can I take
http://www.bls.gov/ooh/
Research, research, research ...
What are you interested in?
How much education/training are you willing to work for?
etc.
I suggest the dart method. Put these on a dart board at a local Pub, blindfold one of the patrons, let him throw.
Or in the 1960s, the IChing method. Get a copy of I Ching, throw it against the wall, if it flops open, that page is your days revelation.
Or, you could try some personal introspection: what you like, dislike, are good at, are not so good at, and what is going to be available as jobs.