There are several places in the program where occupation might be entered. What screen are you referring to? Are you in the Personal Info section? The occupation field there in the Personal Info section will accept anything. It will let me enter "housekeeper" or even nonsense jibberish like "xyxyxyxyx."
So please be more specific about where in the program you are and what you are doing.
Is it on the schedule C? Schedule C line B Business Code is a 6 digit number for your activity. Here are the IRS instructions for Schedule C. Business codes start on page 17.
<a rel="nofollow" target="_blank" href="http://www.irs.gov/pub/irs-pdf/i1040sc.pdf">http://www.irs.gov/pub/irs-pdf/i1040sc.pdf</a>
See the FAQ on Business Codes,
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