If you already know exactly the job to fit your needs, use this stage to investigate and test that 'fit' and thoroughly investigate employment opportunities.
However this assumes you have made the right decision. Occasionally people discover, on closer inspection, that a job they thought they knew all about is different from their expectations. The Graduate Facts Three Survey (1994) which looked at graduates 6 months after university, discovered that 59% of those in work considered their job to be significantly different from what they expected.
Research will also give you a safety net to fall back to if your first choice falls through, or your circumstances change. Similarly occupations are evolving all the time-by remaining focused on just one idea you may be ruling out some options, which could be suitable and interesting for you.